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BY 4.0 license Open Access Published by De Gruyter April 18, 2022

Segmentation of Social Norms and Emergence of Social Conflicts Through COVID-19 Laws

Masaki Iwasaki ORCID logo


In the name of combating COVID-19, many countries have enacted laws that restrict citizens’ freedom of movement and freedom to operate businesses. These laws attempt to use the expressive effects of law and legal sanctions to make people conform to legal norms different from pre-existing social norms. The economic theory of law and social norms predicts that when legal norms deviate significantly from social norms, they can cause people to protest or violate them, leading to a division of social norms and possible social conflicts not only between the state and its citizens but also among people with different beliefs. Using Japan’s COVID-19 laws as a case study, this paper examines under what conditions laws that aim to change social norms can fail and what the side effects are in such cases.

JEL Classification: D70; K32; K42; Z13

1 Introduction

The laws governing measures against COVID-19 in many countries have often proven contrary to pre-existing social norms. A typical example is lockdown laws, which restrict people’s freedom of movement and businesses’ freedom to operate. Though people control their behavior by following individual values and social norms even in their absence, such laws demand behavioral restrictions beyond voluntary efforts and sometimes even use threats of sanctions to change social norms. However, these laws can only function if they meet certain conditions, and once they malfunction, social norms become polarized or multipolar, creating social conflicts among those adhering to different social norms. Many governments have neglected to consider this issue despite its significance since the emergence of the pandemic. This article clarifies the conditions under which COVID-19 laws that attempt to change social norms can work, and what the side effects are if they fail, by applying theoretical models of law and social norms to Japan’s relevant laws.

COVID-19 laws in most jurisdictions have imposed significant costs on society and the economy, while their real benefits are questionable. For example, the benefits of lockdown laws are controversial in terms of their effectiveness in preventing infections (Askitas, Tatsiramos, and Verheyden 2021; Berry et al. 2021) and, at best, are a temporary time-saving measure (Goolsbee and Syverson 2021; Gupta et al. 2021). On the other hand, the costs are far-reaching, including increased incidence of various diseases due to lack of exercise, adverse effects on mental health, and negative impacts on economic activities (Lansiaux et al. 2021). Among them, one of the most critical issues, affecting the very foundation of each society, is the division of social norms and the emergence of social conflicts. As with many other laws, some people support lockdown laws, and some oppose them (Altiparmakis et al. 2021; Bol et al. 2021); what makes lockdown laws different is that people’s social norms may split, and this split may create social conflicts, including discrimination and violence.

It is not unusual for some laws to aim to change social norms and restrict certain behaviors, such as laws banning smoking in public places (Carbonara 2017). These types of laws rarely create serious social conflicts. In many cases, there is a certain scientific rationale for restricting the behavior, and the degree of restriction on people’s freedom is not so great that people opposing a law are likely to protest. It is also unlikely that those who support the law will impose unjust private sanctions, discriminate, or commit violence against violators. However, in the case of COVID-19 laws, the lack of scientific evidence for the behavioral restrictions and the extensive restrictions on people’s freedom have led to large-scale demonstrations and clashes between citizens and police forces around the world. In addition, there have been frequent cases of violence by some citizens against others who do not comply with the government’s orders, including orders to refrain from leaving home or to wear masks.

This paper applies the theory of law and social norms to COVID-19 laws in Japan to discuss the adverse effects of law on social norms. In recent decades, many scholars have developed theories on this topic (Carbonara, Parisi, and Wangenheim 2008, 2012; Cooter 2000; Ellickson 1991; Kahan 2000; McAdams 1997; Pildes 1996; Posner 2000; Sunstein 1996; Zasu 2007). Among them, Carbonara, Parisi, and Wangenheim (2008, 2012 presented innovative formal models to analyze the backlash against unjust laws. They argue that when legal restrictions on people’s behavior lack a rational basis or are far stricter than pre-existing social norm(s) or the level tolerated by most people, the social norm may become polarized or multipolar, resulting in social conflicts, and laws may provoke protests and violations by citizens, contradicting the intended effect of the law.

Applying these theoretical models to the context of COVID-19, we can see that because legal restrictions on freedom of movement and freedom of business operation have a little scientific basis and are stricter than social norms, various groups with different social norms have emerged. Some groups follow the law, while others do not. In addition, as some people protest and violate the law, a situation has arisen in which some deliberately refrain from preventive action they were comfortable taking before observing such protests or violations. Citizens’ precautionary behavior sometimes assumes the cooperation of others, and if social norms work well, a stable coordination equilibrium can be maintained in which citizens cooperate to restrict their behavior. However, in the presence of many protesters or violators, people who observe such lack of cooperation from others will not even take preventive action that they previously took voluntarily.

Carbonara, Parisi, and Wangenheim (2008, 2012 cite the U.S. Prohibition Law, which lasted from 1920 to 1933, to justify the assumptions of their models, but it is not clear to which modern countries and to what kinds of laws the models can be applied. In this regard, the author believes that the practical value of their models is particularly well demonstrated in emergency situations such as the current COVID-19 pandemic. In emergencies, governments tend to make mistakes due to lack of information and experience or misuse emergencies to expand their power (Bjørnskov and Voigt 2021), resulting in unjust laws that deviate from social norms. This paper contributes to the theory of law and social norms by demonstrating that the theory of Carbonara et al. has high explanatory power and provides insights into unjust laws in emergencies, using current Japanese COVID-19 laws as a case study.

The Japanese government has declared a state of emergency multiple times to reduce contact between people, and local governors have asked citizens to stay home and businesses to reduce or halt their operations. In some instances, central and local governments have also asked infected people to cooperate in epidemiological surveys and requested hospitalization. Initially, the government implemented these measures based on the cooperation of citizens and businesses and did not use the threat of legal sanctions. However, in February 2021, the government amended COVID-19 related laws to allow local governors to issue administrative orders to implement these measures and impose administrative fines for violations. While still not permitted to issue compulsory orders to stay at home, they can now order cooperation with epidemiological surveys or hospitalization. They can also order businesses, such as restaurants and bars, to reduce or suspend operations.

After the government repeatedly declared a state of emergency, individuals and businesses gradually ceased compliance with local governors’ requests to restrict activities. This may be due to a growing awareness that behavioral restrictions would not fundamentally solve the problem of infection or a belief that prolonged behavioral restrictions were an unacceptable degree of violation of their rights. They may also have observed others refusing to comply with the government’s request for cooperation and decided that coordination equilibrium was impossible. However, rather than all citizens equally loosening their adherence to restrictions, perhaps because of the segmentation of social norms, groups that do and do not restrict their behavior have emerged. It is noteworthy that even among those who voluntarily restrict behavior, a group of people pejoratively called the self-restraint police (jishuku keisatsu) has emerged, which follows extreme social norms and harasses and assaults those who do not comply with restrictions.[1] In other words, not only have groups adhering to different social norms emerged, but social conflicts have also begun to emerge among these groups.

Furthermore, many people and organizations, including the general public, bar associations (Japan Federation of Bar Associations 2021), and medical associations (Japanese Society of Public Health and Japanese Society of Epidemiology 2021), expressed their opposition to the amendment imposing an administrative fine when an infected person refuses to be hospitalized. They point out that those who are hesitant to be hospitalized generally include non-regular workers who lose income during hospitalization. Fines impose an unnecessary social stigma on infected people when there are less infringing ways to change the incentive structure for hospitalization decisions, such as providing adequate income compensation. In Japan, the government once imposed laws forcibly isolating people affected by leprosy, violating the human rights of patients and their families and creating discrimination among the population. Many believe that Japan is now at risk of repeating this history of misuse of the law.

Japan’s experience will be informative for readers in other countries as well. Even though Japan’s lockdown and other COVID-19 regulations are more lenient than those of other countries, they have nonetheless created a division of social norms and social conflicts, which may have long-term negative effects on society in the future. In countries that adopt stricter regulations, these problems may become more serious. The analysis in this paper can also be applied to COVID-19 policies other than lockdowns, such as mandatory vaccination and vaccine passports.

Section 2 explains the Japanese COVID-19 laws. Section 3 describes the economic theory of infection prevention behavior and the theory of law and social norms. Section 4 applies theoretical models developed by Carbonara, Parisi, and Wangenheim (2008, 2012 to the context of the Japanese COVID-19 experience. Section 5 discusses mechanisms for correcting inappropriate legal norms. Section 6 offers conclusions and discusses the implications of the findings.

2 Japanese COVID-19 Laws

This section describes two major Japanese COVID-19 laws: the Act on Special Measures against Novel Influenza, etc. (Special Measures Act)[2] and the Act on the Prevention of Infectious Diseases and Medical Care for Patients with Infectious Diseases (Infectious Diseases Act).[3] On February 13, 2021, the Japanese government enforced the Act Partially Amending the Act on Special Measures against Novel Influenza, etc., and Other Relevant Acts, which revised the three COVID-19-related laws—namely, the Special Measures Act, the Infectious Diseases Act, and the Quarantine Act. Of these, the first two amendments strongly restrict the rights of people and have essential relationships to social norms; thus, they are the focus of this article. The Special Measures Act regulates the mobility of people and the operations of businesses in an emergency, and the Infectious Diseases Act regulates the epidemiological investigations, hospitalization recommendations, and compulsory hospitalization of infected people.

2.1 Special Measures Act

2.1.1 Outline

We first see the outline of the Special Measures Act. It aims to socially prevent the spread of infectious diseases such as various subtypes of influenza virus. Reflecting on the turmoil in responding to the influenza A virus subtype H1N1 that spread globally in 2009, the government prepared a bill that clarified the legal foundation for countermeasure policies, including the declaration of emergency states against infectious diseases and enforced it in 2013.[4] Since then, fortunately, the government had never declared a state of emergency based on the Special Measures Act until the outbreak of COVID-19. In early 2020, the government applied the act to COVID-19 for a limited period.[5] In April 2020, it declared a state of emergency for the first time, which enabled local governments to take various measures, including requests to stay home and reduce or suspend business operations.

The features of the Special Measures Act are as follows. First, it stipulates the organizational frameworks for emergencies. It describes the conditions for establishing the Government Countermeasures Headquarters, the national-government-level headquarters, when there is a risk of an infection outbreak.[6] The act also stipulates the authority of the heads of Prefectural Countermeasures Headquarters,[7] which are headquarters at the local government level. In Japan, local government areas are called prefectures. As Figure 1 shows, when the Minister of Health, Labor, and Welfare announces a risk of an outbreak of severe infectious disease, the minister must report to the Prime Minister.[8] In response to this report, the Prime Minister will establish the Government Countermeasures Headquarters.[9] If the Government Countermeasures Headquarters is established, then the Prefectural Countermeasures Headquarters will also be established.[10] The heads of the Prefectural Countermeasures Headquarters, which are local governments’ governors, can request necessary cooperation from individuals and organizations.[11] Based on this authority granted by the act, the governors have requested individuals to stay home and businesses to reduce or suspend operations. It should be noted that individual requests are made by prefectural governors, not the Prime Minister, though they cannot make requests before the Prefectural Countermeasures Headquarters are established.

Figure 1: 
Organizational chart at the time of emergency or quasi-emergency declaration.

Figure 1:

Organizational chart at the time of emergency or quasi-emergency declaration.

The second feature of this act is that it stipulates the conditions for declaring a state of emergency. When the Government Countermeasures Headquarters find a nationwide and rapid spread of infectious disease that has or may have a significant impact on people’s lives and the economy, they will declare a state of emergency, announce the outline for emergency measures, including the period and target areas, and report to the Diet.[12] A state of emergency is declared to prevent a national-level pandemic, but it may be targeted to specific prefectures or nationwide, depending on the infection situation.

The prefectural governors of the targeted areas where the state of emergency is declared can request individuals and businesses to take preventive measures, such as requests to stay home for individuals and to reduce or suspend operations for businesses.[13] The governors have no additional measures to enforce compliance by individuals, which remains unchanged before and after the amendment of the act in 2021. For non-compliance by businesses, before the amendment, the governors had the authority to instruct businesses to take requested measures if these measures were particularly necessary for infection prevention.[14] These instructions are legally different from requests in the sense that instructions impose duties to obey while requests do not impose such duties, but instructions do not involve sanctions.

2.1.2 Amendment

As the pandemic dragged on, in February 2021, the government amended the Special Measures Act, applying it to COVID-19 permanently, not temporarily. The major amendments are as follows.

First, under a state of emergency, the prefectural governors can give an order instead of an instruction to businesses if they fail to respond to a governor’s requests for cooperation without a justifiable reason and if the requested measures are particularly necessary for infection prevention.[15] These orders are legally different from instructions in the sense that they involve sanctions. If businesses do not comply with a governor’s order, an administrative fine of 300,000 JPY (2,310 EUR or 2,732 USD) or less can be imposed for the violation.[16] The original bill stipulated a criminal fine with a higher amount, but the act eventually adopted the administrative fine under harsh criticism from the opposing party, lawyers, and commentators, stating that the criminal penalty was too harsh (e.g., Japan Federation of Bar Associations 2021).

Second, the concept of a quasi-emergency state was introduced, in which prefectural governors can take preventive measures before a national-level pandemic occurs. If an infectious disease is spreading in specific areas, not nationwide, and may significantly impact people’s lives and the economy, the Prime Minister announces that the area-focused intensive measures will be carried out in specific prefectures.[17] Table 1 summarizes the differences between emergency and quasi-emergency states. The government classifies possible infection situations into several stages; it declared in principle an emergency state at Stage 4 (infection explosion) and a quasi-emergency state at Stage 3 (rapid infection increase) until the fall of 2021.[18] It considers a variety of indicators, such as hospital bed utilization rate and polymerase chain reaction (PCR) test positive rate, to determine the stage of the current situation.[19]

Table 1:

Differences between emergency and quasi-emergency states.

Emergency state Quasi-emergency state
Triggering condition Stage 4: infection explosion

Bed usage rate: 50%,

PCR positive rate: 10%, etc.
Stage 3: rapid infection increase

Bed usage rate: 20%,

PCR positive rate: 5%, etc.
Target area Prefectures Particular areas within prefectures
Governor’s authority Request individuals to stay home

Request businesses to suspend or reduce business operations
Request individuals to stay home

Request businesses to reduce business operations
Sanction Administrative fine of 300,000 JPY (2,310 EUR or 2,732 USD) Administrative fine of 200,000 JPY (1,540 EUR or 1,821 USD)
Period Up to 2 years and can be extended for no more than 1 year Up to 6 months and can be extended for another 6 months without the limitation for the maximum number of extensions

Prefectural governors can request individuals and businesses to take preventive measures in quasi-emergency states. The important difference in possible preventive measures toward businesses between emergency states and quasi-emergency states is that in quasi-emergency states, requests to reduce business operations are allowed, but requests to suspend them are not allowed;[20] in emergency states, both requests are allowed.[21] In quasi-emergency states, as in emergency states, prefectural governors can give orders to businesses that fail to comply with the governor’s requests without a justifiable reason if the requested measures are particularly necessary for infection prevention.[22] If businesses do not comply with a governor’s order in a quasi-emergency state, an administrative fine of 200,000 JPY (1,540 EUR or 1,821 USD) or less can be imposed for the violation.[23] Emergency states must, in principle, be ended within two years and can be extended for no more than one year,[24] while quasi-emergency states, in principle, must be ended within six months and can be extended for another six months without the limitation for the maximum number of extensions.[25]

The third major amendment is that the act obliges national and local governments to provide financial support to businesses affected by infectious diseases and the preventative measures requested by these governments.[26] Prior to the amendment, the act did not stipulate financial support for business suspension or reduction, but the amendment explicitly imposed on the national and local governments duties for financial support. Relatedly, Article 29, Paragraph 3 of the Constitution stipulates that “Private property may be taken for public use upon just compensation therefor.”[27] Requests to reduce or suspend business operations can be considered examples of the restrictions on private property mentioned in the Constitution, but the national government interprets the financial support in the Special Measures Act as different from the loss compensation stipulated in the Constitution, and the amount of financial support is left to the discretion of the government.[28] The government insists that restrictions on economic activities are allowed to some extent if they are for public health reasons that benefit society as a whole.

2.2 Infectious Diseases Act

2.2.1 Outline

The Infectious Diseases Act stipulates measures for various infectious diseases, such as Ebola hemorrhagic fever, tuberculosis, and influenza, according to their risks. Specifically, the law stipulates (i) the prevention plans of the national and local governments,[29] (ii) information gathering and disclosure for epidemiological surveys,[30] (iii) work restrictions and health examinations for confirmed and suspected patients,[31] (iv) hospitalization recommendations and compulsory hospitalization,[32] (v) disinfection of contaminated places,[33] and (vi) costs to be paid by local governments.[34] After the outbreak of COVID-19, the government decided to apply the Infectious Diseases Act temporarily until the severity of the disease was known. The main provisions applicable to COVID-19 were as follows.

First, the law stipulates the authority of prefectural governors to conduct an epidemiological survey to track infection routes, find clusters, and investigate symptoms when confirming an infected person.[35] The governors can have prefectural employees ask questions of and investigate confirmed and suspected patients, who are obliged to make efforts to cooperate in the investigation.[36] Before the amendment in 2021, there were no sanctions for failing to obey the obligation. Second, the law stipulates the hospitalization of patients. Prefectural governors can recommend hospitalization to confirmed patients.[37] Prior to the amendment, hospitalization could be recommended to all patients without distinction based on the risk of health aggravation, but this point has been amended as explained below. If a patient fails to follow the governor’s recommendation, the governor can compulsorily hospitalize the patient.[38] The length of hospital stay should not exceed 72 hours but can be extended by 10 days if necessary.[39] Before the amendment, there were no penalties for violating such hospitalization measures.

2.2.2 Amendment

From February 2021, the amended Infectious Diseases Act came into effect. The law was permanently applied to COVID-19, and among the five levels of health risk classification, COVID-19 was classified into the group of the second-highest risk, to which tuberculosis also belongs.[40] The major amendments are (i) the introduction of penalties for violations of the obligation to cooperate in epidemiological investigations and (ii) the amendments to hospitalization provisions, such as the new triggering conditions of hospitalization measures and the introduction of penalties for violating them.

Specifically, the first amendment is that, to achieve effective epidemiological investigations, the prefectural governors can now order confirmed and suspected patients to cooperate with the investigation if they refuse to answer, give a false answer, or interfere with the investigation without a justifiable reason.[41] If they fail to follow these orders, the governors can impose an administrative fine of up to 300,000 JPY (2,310 EUR or 2,732 USD).[42]

Second, the amendments to hospitalization provisions are as follows. The prefectural governors can recommend hospitalization to patients aged 65 and over and patients at high risk, such as those with respiratory diseases.[43] The governors also can request low-risk patients for cooperation to stay in accommodations or homes until recovery;[44] to those who do not respond to such requests, the governors can recommend hospitalization.[45] For those who do not accept the governor’s recommendations for hospitalization, the governors can compulsorily hospitalize them regardless of their health risks.[46] When patients escape from compulsory hospitalization or escape from hospitals during hospitalization, the governors can impose an administrative fine of up to 500,000 yen (3849 EUR or 4554 USD).[47]

3 Theory of Law and Social Norms

This section will look at the economic theory of infection prevention behavior of people and businesses and the theory of law and social norms. These theories will then be applied to the context of Japanese COVID-19 laws in the next section.

3.1 Economic Theory of Infection Prevention Behavior

For individuals, the examples of infection prevention actions against COVID-19 are maintaining social distance, wearing a mask, and staying home when possible. For businesses where customers visit, including restaurants, bars, and shopping malls, examples include installing a ventilation system, disinfecting the inside of buildings, and limiting the number of visitors. Why do people and businesses take these actions? From an economic point of view, if the benefits of taking a particular preventive action outweigh the costs, then a person or business will take that action. The benefits of staying home for individuals, for example, may include maintaining health by avoiding infection risks and ensuring the safety of family members, and the costs may be inconvenience and loss of travel opportunities. The benefits to businesses of installing a ventilation device may be gaining a reputation of safety and mitigating the risk of business suspension due to the discovery of infection cases. The costs may include the installation costs of a ventilation system.

To assess the benefits and costs of preventive actions, people need risk information. They refer to information, such as infection and death statistics, provided by their government and observe the infection status of their family and friends. They also refer to the data published by foreign countries and international organizations. However, the origin and infection mechanism of COVID-19 has not been elucidated, and a reliable method for detecting infection has not been established. Therefore, it is hard to say whether governments and international organizations have provided sufficient information. People must take preventive actions on the premise that risk information may be inaccurate. Consequently, in assessing the benefits and costs of preventive actions, people place more weight on the information gained from observing the behavior of others than they would when risk information is accurate (on informational cascades, see Bikhchandani, Hirshleifer, and Welch 1992).

People change their preventive behavior according to not only risk information but also social norms. Social norms influence people’s benefit-cost structure. For instance, staying home may be effective for individuals in temporarily protecting themselves but, without cooperation in their community, cannot lead to their long-term safety. It would not make sense for only one individual to stay home; all people in a region or country need to work together to take the same action. In this regard, cooperation based on social norms plays an important role in COVID-19 infection prevention behavior. If there is a social norm encouraging cooperation among people, the benefits of taking preventive action would increase because the actions of individuals can lead to safety in their community as a result of cooperation.

In sum, people take protective actions based on risk information and social norms. When governments gauge that the levels of preventive behavior of people are below socially optimal levels, they can use the law to change the behavior by influencing social norms. For this reason, we will next examine the relationship between law and social norms.

3.2 Theory of Law and Social Norms

In law and economics, social norms generally refer to the regularities of behavior regardless of causes but often are used in a narrower sense as the regularities of behavior due to a specific cause (Cooter 2000; Ellickson 1991; McAdams 1997). There are three main reasons why people obey social norms: (i) cooperative equilibrium, (ii) non-legal sanctions, and (iii) the internalization of the obligations imposed by social norms (Carbonara 2017). First, (i) when there are multiple equilibria, following social norms may maximize gains and result in the Nash equilibrium. People adhere to a cooperative equilibrium because they believe that others also comply. Therefore, when others are not expected to cooperate, a cooperative equilibrium cannot be maintained, and social norms may change. Second, as Cooter (2000) points out, (ii) people adhere to social norms for fear of non-legal sanctions such as social sanctions. Moreover, (iii) if people internalize the obligations imposed by social norms and have a preference to obey such obligations, they are willing to comply with social norms.

Next, consider the role of law in prohibiting or promoting certain acts without sanctions. As we have already seen, before their amendments, the Special Measures Act and the Infectious Diseases Act attempted to change the behavior of individuals and businesses without sanctions. Laws without sanctions have so-called expressive effects, making people internalize legal norms to obey (Cooter 2000; McAdams 1997; Sunstein 1996). There are generally three different channels in which laws affect behavior by expressive effects (Carbonara 2017). First, laws can change the social meaning of a particular action. Second, laws can create so-called focal points, drawing people’s attention to certain behaviors, changing their expectations of others’ behaviors, and making them favor cooperation. Third, laws can make people internalize the values embodied in the laws (legal norms) and change their preferences.

If legislators want to achieve particular legal norms that differ from social norms, they can use laws without sanctions to gently bring social norms closer to specific legal norms through the expressive effects. For example, if legislators want to change the activity level of a particular action influenced by social norms, the legislator can introduce a specific law without sanctions to change the social norms. However, because the law does not involve sanctions, it can have only a weak effect on people’s behavior. So can social norms always be forced closer to specific legal norms by introducing laws with sanctions? The answer is no.

Carbonara, Parisi, and Wangenheim (2008, 2012 developed the seminal theoretical models to describe the potential and danger of laws that try to change social norms. Even if a law with sanctions is introduced to ban certain acts, if people question or disagree with its legitimacy, some may not only violate but also protest it. If many people observe such violations and protests, they may suspect the legitimacy of legal norms embodied in the law, and the costs of violation and participation in protests, such as psychological costs, will decrease. Consequently, legislators may not achieve desired legal norms, and the actions that they want to prohibit may increase. Therefore, if legal norms embodied in specific laws with sanctions deviate from social norms greatly, the laws can cause a backlash. The original social norms may be partially or completely destroyed. For example, there may be two groups: a group that obeys the law (while some members question the legitimacy of the law) and a group that does not.

We can derive important policy implications from the models of Carbonara, Parisi, and Wangenheim (2008, 2012. When laws divide social norms, conflicts may arise between social groups that follow different social norms. Many governments have ignored this point, but it can have enormous social costs. Some people may force others to follow their own social norms through threats, assault, or other unjustified means, because the more people who follow the social norms they believe in, the higher their payoff. Those who follow the majority social norm may discriminate against those who follow the minority social norm. In fact, under the current pandemic, not only government–citizen conflicts but also citizen–citizen conflicts have arisen in many countries over COVID-19 policies such as lockdown and vaccine passports (Dada et al. 2021; Jedwab et al. 2021).

4 Application of the Theory to the Japanese COVID-19 Context

Let us apply the above theoretical framework to the Japanese context. We will examine the impact on society of the Special Measures Act in Section 4.1 and the Infectious Diseases Act in Section 4.2, using data.

4.1 Impacts of the Special Measures Act on Japanese Society

4.1.1 Behavioral Restrictions Imposed on Residents and Businesses

In Japan, there have been several emergency and quasi-emergency declarations since 2020. In the capital city of Tokyo, four emergency declarations and two quasi-emergency declarations have been issued. The requests to individuals and businesses were almost the same in all prefectures, with individuals being asked to refrain from going out and businesses being asked to reduce or suspend operations.

Let us look at specific restrictions imposed on residents and businesses. For example, in Tokyo’s fourth declaration of a state of emergency, residents in all areas of the city were asked to refrain from going out and moving around unnecessarily, including during the daytime.[48] Specifically, they were requested to refrain from going out in principle, except when necessary for the maintenance of their lives and health, such as going to medical institutions; shopping for food, medicine, and daily necessities; going to work; and exercising or walking outdoors.[49] In addition, the Governor of Tokyo requested the following: refraining from going out after 8:00 p.m. for non-essential reasons; avoiding crowded places and times; strictly refraining from using restaurants and other establishments that do not have thorough infection control measures in place or that do not respond to requests to close or reduce business hours; refraining from returning to one’s hometown or traveling to other prefectures; refraining from unnecessary travel to areas where the infection is spreading; and refraining from activities with a high risk of infection, such as drinking in groups on the street or in parks.

As for businesses, the Governor of Tokyo requested that restaurants that serve alcoholic beverages and karaoke facilities be closed and that restaurants that do not serve such items reduce their business hours (to 5:00–20:00).[50] In addition, she requested restaurants to conduct infection tests on their employees, restrict the number of guests, inform guests to wear masks, ventilate facilities, and use acrylic panels and other measures to prevent the spread of saliva droplets. Shopping centers were also asked to reduce their opening hours, depending on the size of their premises.[51] Event venues were asked to reduce their maximum capacity by half.[52]

4.1.2 Fulfillment of Preconditions for Applying the Models

Before examining the data on the impact of the law on society, let us examine whether the assumptions for applying the models of Carbonara, Parisi, and Wangenheim (2008, 2012 to the Japanese context are met. The key assumptions of their models are as follows. (i) People have their own beliefs about restricting or promoting certain behaviors. (ii) People interact with each other to influence and change their beliefs. (iii) The larger the proportion of people with a particular belief, the more likely an individual is to be influenced by that group. (iv) When a legal norm diverges significantly from one’s belief, one will violate or protest. (v) There are physical and psychological costs to violating or protesting, but these costs decline as the proportion of people who disagree with the legal norm increases.

People have their own beliefs about acceptable levels of restrictions on freedom of movement and freedom to operate and may change their beliefs as a result of exposure to the beliefs of others through communication with family, friends, and colleagues or the news. It is natural to assume that the more people who hold a particular belief, the more influential that belief will be. Then, we can consider assumptions (i) through (iii) satisfied. In addition, if the beliefs of individuals and businesses diverge from legal norms, they may not comply with local governors’ requests to stay home or with requests or orders to reduce business hours. It is also possible for businesses to file a lawsuit or take other protest actions, claiming that governors’ orders violate the freedom of business guaranteed by the Constitution. The more individuals who refrain from going out, the greater the psychological cost of going out, and the more businesses that refrain from operating normally, the greater the psychological cost of operating would be. Therefore, assumptions (iv) and (v) are satisfied.

Since the assumptions for applying the models are met, we examine whether, as the models predict, there has been an increase in violating and protesting behavior by individuals and businesses, a division in social norms, the emergence of groups with different beliefs, and social conflicts between groups. If the legal norms that Japan’s COVID-19 laws seek to introduce significantly diverge from social norms, then such backlashes predicted by the models should have emerged.

4.1.3 Data and Interpretation

Table 2 shows the specific periods of emergency and quasi-emergency for each prefecture and the average rate of decrease in the number of people moving during those periods. It shows the rate of decrease in movement when the amount of people moving during normal times before the pandemic is set to 100. For example, in Tokyo, four emergency declarations and two quasi-emergency declarations were made. Since risk conditions such as the number of infected people and the utilization rate of hospital beds, which trigger emergency declarations, vary from prefecture to prefecture, the number and duration of emergency and quasi-emergency states also vary from prefecture to prefecture. The table shows that in the case of multiple emergency declarations, the first declaration reduced the movement of people the most, while the reduction became smaller in the second declaration. In many prefectures, the reduction in the third and fourth declarations was the same as or even smaller than the second declaration.

Table 2:

Average rate of change in human mobility during emergency and quasi-emergency states in each prefecture.

Prefecture Emergency Avg. Quasi-emergency Avg. Prefecture Emergency Avg. Quasi-emergency Avg. Prefecture Emergency Avg. Quasi-emergency Avg.
Hokkaido 2020/4/16–5/25 −24 2021/5/9–5/15 −13 Osaka 2020/4/7–5/21 −31 2021/4/5–4/24 −19 Fukuoka 2020/4/7–5/14 −28 2021/6/21–7/11 −16
2021/5/16–6/20 −16 2021/6/21–7/11 −5 2021/1/14–2/28 −25 2021/6/21–8/1 −20 2021/1/14–2/28 −22 2021/8/2–8/19 −25
2021/8/27–9/30 −7 2021/8/2–8/26 −4 2021/4/25–6/20 −27 2021/5/12–6/20 −21
Miyagi 2020/4/16–5/14 −27 2021/4/5–5/11 −13 2021/8/2–9/30 −25 2021/8/20–9/30 −20
2021/8/27–9/12 −14 2021/8/20–8/26 −13 Hyogo 2020/4/7–5/21 −27 2021/4/5–4/24 −13 Kumamoto 2020/4/16–5/14 −23 2021/5/16–6/13 −18
2021/9/13–9/30 −6 2021/1/14–2/28 −20 2021/6/21–7/11 −14 2021/8/8–9/30 −18
Fukushima 2020/4/16–5/14 −21 2021/8/8–9/30 −8 2021/4/25–6/20 −19 2021/8/2–8/19 −20 Miyazaki 2020/4/16–5/14 −22 2021/8/27–9/30 −11
Tokyo 2020/4/7–5/25 −43 2021/4/12–4/24 −23 2021/8/20–9/30 −15 Kagawa 2020/4/16–5/14 −28 2021/8/20–9/30 −17
2021/1/8–3/21 −30 2021/6/21–7/11 −24 Kyoto 2020/4/16–5/21 −34 2021/4/12–4/24 −18 Kagoshima 2020/4/16–5/14 −23 2021/8/20–9/30 −15
2021/4/25–6/20 −28 2021/1/14–2/28 −25 2021/6/21–7/11 −18 Kochi 2020/4/16–5/14 −24 2021/8/27–9/12 −17
2021/7/12–9/30 −29 2021/4/25–6/20 −24 2021/8/2–8/19 −24 Saga 2020/4/16–5/14 −27 2021/8/27–9/12 −18
Kanagawa 2020/4/7–5/25 −31 2021/4/20–8/1 −15 2021/8/20–9/30 −22 Nagasaki 2020/4/16–5/14 −25 2021/8/27–9/12 −17
2021/1/8–3/21 −22 Mie 2020/4/16–5/14 −30 2021/5/9–6/20 −19 Okinawa 2020/4/16–5/14 −43 2021/4/12–5/22 −25
2021/8/2–9/30 −21 2021/8/27–9/30 −24 2021/8/20–8/26 −22 2021/5/23–9/30 −31
Saitama 2020/4/7–5/25 −27 2021/4/20–8/1 −14 Gifu 2020/4/16–5/14 −32 2021/5/9–6/20 −13 Akita 2020/4/16–5/14 −9
2021/1/8–3/21 −19 2021/1/14–2/28 −21 2021/8/20–8/26 −16 Aomori 2020/4/16–5/14 −16
2021/8/2–9/30 −18 2021/8/27–9/30 −14 Fukui 2020/4/16–5/14 −24
Chiba 2020/4/7–5/25 −28 2021/4/20–8/1 −14 Shiga 2020/4/16–5/14 −28 2021/8/8–8/26 −16 Iwate 2020/4/16–5/14 −15
2021/1/8–3/21 −21 2021/8/27–9/30 −15 Nagano 2020/4/16–5/14 −28
2021/8/2–9/30 −19 Ishikawa 2020/4/16–5/14 −30 2021/5/16–6/13 −17 Nara 2020/4/16–5/14 −28
Gunma 2020/4/16–5/14 −25 2021/5/16–6/13 −11 2021/8/2–9/30 −13 Niigata 2020/4/16–5/14 −20
2021/8/20–9/30 −12 2021/8/8–8/19 −14 Toyama 2020/4/16–5/14 −25 2021/8/20–9/12 −10 Oita 2020/4/16–5/14 −25
Ibaraki 2020/4/16–5/14 −28 2021/8/8–8/19 −23 Yamanashi 2020/4/16–5/14 −33 2021/8/20–9/12 −11 Shimane 2020/4/16–5/14 −22
2021/8/20–9/30 −18 Ehime 2020/4/16–5/14 −21 2021/4/25–5/22 −19 Tokushima 2020/4/16–5/14 −21
Tochigi 2020/4/16–5/14 −27 2021/8/8–8/19 −15 2021/8/20–9/12 −17 Tottori 2020/4/16–5/14 −20
2021/1/14–2/7 −23 Hiroshima 2020/4/16–5/14 −28 2021/8/20–8/26 −20 Wakayama 2020/4/16–5/14 −23
2021/8/20–9/30 −14 2021/5/16–6/20 −22 Yamagata 2020/4/16–5/14 −18
Shizuoka 2020/4/16–5/14 −31 2021/8/8–8/19 −22 2021/8/27–9/30 −19 Yamaguchi 2020/4/16–5/14 −23
2021/8/20–9/30 −21 Okayama 2020/4/16–5/14 −23 2021/8/20–8/26 −17
Aichi 2020/4/16–5/14 −28 2021/4/20–5/11 −14 2021/5/16–6/20 −19 2021/9/13–9/30 −12 1st Emer. Avg. −26 1st Quasi. Avg. −16
2021/1/14–2/28 −20 2021/6/21–7/11 −14 2021/8/27–9/12 −20 2nd Emer. Avg. −21 2nd Quasi. Avg. −16
2021/5/12–6/20 −17 2021/8/8–8/26 −22 3rd Emer. Avg. −19 3rd Quasi. Avg. −15
2021/8/27–9/30 −18 4th Emer. Avg. −21

  1. The time period of the data is 2020 and 2021. The columns of “Avg.” (average) give the percentage changes in visitors (or time spent) at the following locations compared to the day-of-week baseline: (1) retail and recreation locations, (2) parks, (3) transit stations, and (4) workplaces. The percentage changes for these four locations were averaged. The day-of-week baseline represents the standard value for the corresponding day of the week. Specifically, it is the median value for each day of the week for the five weeks from January 3 to February 6, 2020. The numbers in the lower right-hand corner of the table show the average values of the average changes in the n-th emergency or quasi-emergency states for each prefecture. Source: The data for mobility was taken from Google COVID-19 Community Mobility Reports ( The data for the emergency and quasi-emergency periods of each prefecture was taken from the website of Keyword marketing (

The quasi-emergency declarations showed smaller decreases in the movement of people than the emergency declarations. This is a natural result, considering that a quasi-emergency declaration is issued in a situation where the risk of infection, such as the number of infected people and hospital bed utilization, is lower than that of the emergency declaration. The extent to which the movement of people changes when a quasi-emergency declaration is issued multiple times varies from prefecture to prefecture. On average, the effect on migration did not change much when a state of quasi-emergency was declared for the second or third time.

It is important to note that the reduction in human mobility in emergency and quasi-emergency situations includes the result of people’s voluntary response to changes in the risk situation, in addition to the effect of government declarations. Watanabe and Yabu (2021a, b) distinguish between the effect of people reducing their outings in response to government requests (intervention effect) and the effect of people voluntarily reducing their outings based on risk information (information effect). They estimated the magnitude of these effects in Japan, although using only 2020 data, and showed that the information effect was larger than the intervention effect. In Table 2, the considerable differences in mobility during emergency and quasi-emergency periods across prefectures may be explained by the fact that the information effect differed considerably across prefectures. If the risk of infection differs among prefectures, and if people’s risk judgments tend to be prefecture-specific, the information effect may differ among prefectures. In addition, since the degree of compliance with legal norms may differ among prefectures, the intervention effect may also vary among prefectures.

Figure 2 shows the relationship between the movement of Tokyo residents and the emergency and quasi-emergency states. In Tokyo, an emergency was declared four times and a quasi-emergency twice. During the first state of emergency, the movement of people decreased by 40% on average, but during the subsequent states of emergency, the decrease was only about 30% on average. Businesses such as restaurants and shopping malls were asked to temporarily close or reduce their business hours during the states of emergency and quasi-emergency, and initially, most complied. However, as the emergency and quasi-emergency declarations were repeated, some businesses gradually ignored the requests and operated normally (Nakatsugawa et al. 2021). As a result, many prefectures have issued orders to restaurants that do not comply with the requests and have imposed fines on restaurants that do not comply with the orders (Tokyo Shimbun 2021c).

Figure 2: 
Changes in human mobility in Tokyo (February 15, 2020 – December 24, 2021). The “Mobility” data show the percentage changes in visitors (or time spent) at the following locations compared to the day-of-week baseline: (1) retail and recreation locations, (2) parks, (3) transit stations, and (4) workplaces. The percentage changes for these four locations were averaged. The day-of-week baseline represents the standard value for the corresponding day of the week. Specifically, it is the median value for each day of the week for the five weeks from January 3 to February 6, 2020. The data for “Moving Average (7 days)” represent the average changes over the past 7 days for each day. “E” and “Q” denote the duration of emergency and quasi-emergency states, respectively. Source: Google COVID-19 Community Mobility Reports (

Figure 2:

Changes in human mobility in Tokyo (February 15, 2020 – December 24, 2021). The “Mobility” data show the percentage changes in visitors (or time spent) at the following locations compared to the day-of-week baseline: (1) retail and recreation locations, (2) parks, (3) transit stations, and (4) workplaces. The percentage changes for these four locations were averaged. The day-of-week baseline represents the standard value for the corresponding day of the week. Specifically, it is the median value for each day of the week for the five weeks from January 3 to February 6, 2020. The data for “Moving Average (7 days)” represent the average changes over the past 7 days for each day. “E” and “Q” denote the duration of emergency and quasi-emergency states, respectively. Source: Google COVID-19 Community Mobility Reports (

The facts reviewed so far indicate that the extent to which individuals and businesses limit their behavior has decreased over time. So how has the infection risk changed? As Figure 3 shows, the daily numbers of infections and deaths in Japan have gone through several cycles of increase and decrease, but the numbers of infections and deaths in 2021 are much higher than in 2020. The vaccination rate has risen sharply since the second half of 2021, but the effectiveness of the vaccines has not been robust (Cohn et al. 2022; Pouwels et al. 2021), and it does not appear that people believe that the vaccine has significantly reduced their objective risk. In addition, the degree of behavioral refrain had already decreased during the emergency and quasi-emergency states in the first half of 2021, before the vaccination rate increased.

Figure 3: 
New cases per million, new deaths per million, and people vaccinated per hundred (January 22, 2020 – December 24, 2021). Source: Ritchie et al. (2020).

Figure 3:

New cases per million, new deaths per million, and people vaccinated per hundred (January 22, 2020 – December 24, 2021). Source: Ritchie et al. (2020).

The fact that the number of infections and deaths has risen, but the degree of behavioral restrictions has decreased, allows for several interpretations. It is possible that people were more cautious at the beginning of the pandemic because there was less information about the virus and more uncertainty about the probability of infection and symptoms. Over time, people’s risk assessment may have changed, and their self-restraint behavior may have changed as well. However, it is also very possible that repeated emergency and quasi-emergency declarations have changed people’s social norms and behavior.

Based on the above facts, there are several possible reasons why the emergency and quasi-emergency declarations have been less influential in restricting the behavior of individuals and businesses. They may have learned that behavioral restriction is ineffective and does not fundamentally solve the spread of infection. For example, in Tokyo, even once a state of emergency ended, the next state of emergency was declared within a month or several months. It is no wonder that more and more people have been fed up with the repetition of unrewarding efforts.

Individuals and businesses may also have thought that behavioral restriction for a long period was not an acceptable level of rights violation. In Tokyo, the duration of each emergency was a few months, but in total, its residents were asked to restrict their behavior for more than one out of the past two years. Some businesses, such as restaurants and bars, refused to comply with the local governors’ requests because the local governments’ compensation for temporary closure or reduction of business hours was inadequate, and the time between application and payment was too long (Nakatsugawa et al. 2021). In addition, they may have thought that since they had taken the infection prevention measures requested by the local governments, such as installing ventilation and acrylic panel devices, they had reduced the risk sufficiently, and there was no need to close or reduce business hours. In fact, a listed company that operates restaurants filed a lawsuit over the Tokyo governor’s order to limit business hours (Kyodo News 2021).

Furthermore, as the number of people who did not comply with the government’s request gradually increased, some people may have observed this and thought that the coordination equilibrium could not be maintained. By staying home, they can at least improve their own risk of infection, but not the situation in their community or the country. It is also possible that not all people restricted their behavior to the same extent, but that some restricted and others did not and that the proportion of the latter group gradually increased.

4.1.4 Segmentation of Social Norms and Emergence of Social Conflicts

An important, though difficult to recognize, problem with emergency and quasi-emergency declarations is that they may divide social norms and cause conflicts among those with different values. For example, in a survey conducted in September 2021 on 1,200 men and women between the ages of 15 and 69 (NHK 2021), 19.4% of respondents answered that they refrained from outdoor activities, such as going out or eating out, less than they did when the nationwide state of emergency was declared in all prefectures in April 2020; 54% of the respondents answered that their degree of self-restraint has not changed; 26.6% answered that they have become more self-restrained. These results indicate that social norms may have gradually become fragmented.

While there may not be a problem if the different social norms simply coexist, some groups are becoming more radical in imposing their values on others. In a survey of 1,032 people who returned to the countryside from cities with poor infection status during the summer vacation of 2020 (General Research 2020), one in five was harassed by rural residents in some way, such as being told not to come back, having pebbles thrown at them, or receiving anonymous letters of condemnation in their mailboxes. At that time, the state of emergency was over, but there remained certain individuals who thought that people should refrain from going out. In addition, although it is not required by law to wear masks, some people force others who are not wearing masks to wear them. There have been cases in which people who were scolded about not wearing a mask became angry and assaulted the person who scolded them (Asahi Shimbun 2021). In addition, there have been those who have put up posters with threatening messages on restaurants and bars that do not respond to governors’ requests to close or reduce business hours and spread photos of such posters on social networking sites to shame these businesses (Tokyo Shimbun 2021a).

Those who impose private sanctions on those who do not comply with the government’s request for cooperation in restricting behavior are often called jishuku keisatsu (self-restraint police), and they have become a major social problem (Osaki 2020; Wright 2021). They believe that the norms they believe in are legitimate and attempt to force others to cooperate in ways beyond what is legally permissible, thinking that private enforcement of the norms will improve social welfare. Social sanctions against those who deviate from social norms have been observed everywhere, but it is not always the case that the social norm in question is legitimate or that the degree of social sanction or the form of private enforcement is optimal. The self-restraint police derive utility from private sanctions because their own utility increases as more people follow their norms, but they do not take into account any disutility they may impose on others. Coercion by the self-restraint police can be considered a crime of assault, injury, or destruction of property, so it will be necessary to strengthen control over illegal private sanctions.

The concept of “self-restraint police” is not a new one in Japan. During World War II, Japan had organizations of local residents called tonari gumi (neighborhood association) (Masland 1946). In these organizations, residents monitored each other to check deviants from the social norms of the majority at the time and imposed private sanctions on them.

The concept of tonari gumi is said to have originated from a voluntary mutual support organization of local residents that existed in the Edo period (between 1603 and 1867) and was misused by the government as a tool for procuring supplies and controlling residents during World War II.[53] In 1940, in accordance with the “Guideline of Control and Enhancement of Village Community Associations and District Associations [Burakukai Chonaikai Tou Seibi Youryou]” (Home Ministry Instruction No. 17), the government set up groups of five to 10 households to promote unity among the local residents and have them work together to provide supplies, distribute controlled items, and defend against air raids. The government also used neighborhood organizations to police the people’s thoughts by having residents monitor each other, and residents sometimes tipped off the police to arrest those who had anti-war thoughts. In 1947, after the end of World War II, the General Headquarters of the Supreme Commander of the Allied Powers banned the tonari gumi system.

In contrast to the group of people who voluntarily restrict their activities, a group who refuse to adhere to restrictions has also emerged. The cumulative number of infections and deaths in Japan is 13,743 per million population and 146 per million population, respectively, as of December 31, 2021. The health impacts of COVID-19 are not significantly different from those of many other diseases for most Japanese (Onozuka et al. 2022; Taniguchi et al. 2022). When comparing the benefits and costs of behavioral constraints, no convincing evidence has ever been submitted that the benefits outweigh the costs. Although it may be extreme to take no measures at all, it is no wonder that some believe that what is now believed to be a pandemic was never such a great risk.

The emergence of negative groups about behavioral restrictions may also be attributed to the growing public distrust of the government and COVID-19 laws. First, although the government asked people to refrain from eating and drinking late at night during the declaration of a state of emergency, there were several cases of politicians visiting nightclubs and violating the rule (Takemoto, Kaneko, and Murakami 2021). Also, in the summer of 2021, the government forced the hosting of the Tokyo Olympics while in principle refusing new entry to foreigners from all countries and regions. However, about 1,700 people, or about 85% of the Tokyo Olympics and Paralympics officials who entered the country in April and May of the same year, entered under a “special entry” exemption from the quarantine requirement introduced as a border control measure against the COVID-19 (Tokyo Shimbun 2021b). It is likely that many citizens gradually grew to distrust the government for its stance of requesting citizens to restrict their activities while giving special treatment to a few people. In fact, in an August 2021 poll, during the state of emergency in several prefectures, the administration’s approval rating dropped to 34%, while disapproval of its COVID-19 policy rose to 64% (Mizorogi 2021).

In addition, the government’s policy to stimulate demand for travel and dining out in the fall of 2020 may have added to the public’s distrust of the government and its COVID-19 policy. This policy, called the “Go To Campaign” (Japanese English), is an economic policy of the Japanese government aimed at stimulating demand for travel, food service, and events in Japan and reviving the economic damage caused by the declaration of the state of emergency. A total of 2.7 trillion JPY (21 billion EUR or 25 billion USD) was allocated for this project (Hatsumi and Takagi 2021). The campaign was designed to subsidize domestic travel and dining out, but soon after its implementation, the number of infected people increased, and a new state of emergency was declared, raising questions about the coherence of the policy. It is possible that some citizens read the wrong message from these policies and came to believe that self-restraint was no longer important.

According to a survey by an organization of the Tokyo Metropolitan Government, most people are voluntarily restricting their activities to prevent infection even after the declaration of the state of emergency (Tokyo Center for Infectious Disease Control and Prevention 2021). For example, even in October 2021, when the number of infected people drastically decreased, 95% of the respondents reported voluntarily wearing masks, while 88% were refraining from dining out in a large group.

The number of people who follow extreme norms, including both the self-restraint police on the one hand and those refuse all preventive actions on the other, seems to be currently limited. However, if a state of emergency is declared again because of a new cycle of infection increase, the number of people who hold intermediate social norms may decrease, and the extreme adherents may increase, leading to polarization or further division of social norms. In such a situation, those who impose their values and norms on others may increase. Different groups may develop mutual sentiments of hatred, and social conflicts may intensify. In World War II, the Japanese government took advantage of this psychological tendency to achieve its political goals, and we need to be aware of the danger of such a situation arising in the future.

4.2 Impacts of the Infectious Diseases Act on Japanese Society

In the case of the Infectious Diseases Act, people have beliefs about acceptable standards regarding the imposition of epidemiological investigations and hospitalization measures on individuals, as they do about all restrictions that are closely related to their own human rights. They will also influence each other’s beliefs and may disobey a prefectural governor’s order or express protest. Therefore, the preconditions for applying the models of Carbonara et al. are met.

To date, there have been no cases in which the government has imposed a fine on individuals for refusing to cooperate in epidemiological investigations or not responding to hospitalization recommendations. Indeed, during the periods of rapid increase in infection, there were many patients who could not be hospitalized even if they wanted to be and were forced to recuperate at home due to the low availability of hospital beds (Tsukimori 2021). For this reason, the revision of the Infectious Diseases Act has not emerged as a major social issue until now. However, according to a survey, 42% of respondents were opposed to the revision of the Infectious Diseases Act, while 44% were in favor of it, indicating that the public has not necessarily accepted the revision (Nagasaki Shimbun 2021).

In fact, when the government announced the proposed amendments to the Infectious Diseases Act, lawyers and doctors from major associations expressed their opposition to imposing sanctions on those who do not cooperate with epidemiological investigations or follow hospitalization recommendations (Japan Federation of Bar Associations 2021; Japanese Society of Public Health and Japanese Society of Epidemiology 2021). The original amendment was to impose criminal fines, but due to the strong opposition, the government compromised on administrative fines instead. However, even if the sanction is in the form of administrative fines, the opposition is still strong.

One of the common reasons given by those who oppose the revision of the Infectious Diseases Act is that the content of the revision is inconsistent with the intent and purpose of the law. In Japan, the government and society have historically discriminated against patients suffering from infectious diseases such as leprosy and violated their human rights (Leprosy is a chronic infectious disease caused by Mycobacterium leprae that mainly affects the skin and nerves.). Taking a lesson from this history, the government enacted the Infectious Diseases Act in 1998 in order to improve measures against infectious diseases while respecting human rights. Article 2 of the law clearly states that the government shall be deeply aware of the situation of patients and their families and take measures against infectious diseases while respecting the human rights of these people.

The Japanese government forcibly confined leprosy patients in isolation facilities for nearly a century from the early 1900s to the end of the century (Sato 2002). Once in quarantine, patients were rarely allowed to leave, were forbidden to have children, and were sterilized (Miyasaka 2014). The families of patients faced social discrimination, including difficulties in marriage (Human Rights Bureau of the Ministry of Justice and Center for Human Rights Education and Training 2020). From the 1930s to the 1960s, the prefectures conducted a social movement, the prefectural-wide Zero Leprosy Campaign (Muraiken Undo), which aimed to have all leprosy patients isolated and forcibly housed in sanatoriums and to wipe patients out from the prefectures (Miyasaka 2014). This campaign encouraged citizens to report any leprosy patient found living in hiding to the police for forcible confinement and functioned as a surveillance system for leprosy patients by the general public.

Commentators have pointed out the similarities between the current situation and that which led to discrimination against people affected by leprosy (Okamoto 2020; Suzuki, Iizuka, and Lefor 2021). Currently, there is discrimination against people infected with COVID-19, their families, and health care workers because of the misconception that they can transmit the disease even in situations in which there is no objective risk of infection, and various forms of harassment occur in workplaces and schools (Denyer and Kashiwagi 2020; Ministry of Health, Labour and Welfare of Japan 2020; Yoshioka and Maeda 2020). The health impacts of COVID-19 are not high for most Japanese people (Onozuka et al. 2022; Taniguchi et al. 2022), but the government is stoking public fear by emphasizing the risk more than necessary. By imposing sanctions for refusal of epidemiological studies and hospitalization recommendations, it is attempting to instill in the public the perception that COVID-19 patients need to be physically and socially isolated. Such policies are likely to change people’s social norms in the wrong direction, creating discrimination against patients and causing overreaction to infection risks and giving rise to extreme groups such as the self-restraint police.

Leaving aside the question of whether patients need to be hospitalized, in considering the means to achieve the goal from an economic perspective, if the personal benefits to individuals of epidemiological investigations and hospitalization measures outweigh the costs, they will voluntarily cooperate. The main reason often mentioned for refusing to cooperate with epidemiological studies and hospitalization is the loss of income for non-regular workers during their absence from work. On the one hand, it may be true that people should not go to work when there is a risk of infecting others. On the other, it would not be a rational policy to forcibly hospitalize people, even those infected, in a situation where their livelihood is not adequately guaranteed. Suppose an income compensation system is developed that allows non-regular workers to be hospitalized without concern about reduced income. In that case, the benefits of epidemiological studies and hospitalization measures will outweigh the costs, and people would voluntarily cooperate.

The amendment to the Infectious Diseases Act uses the means of legal sanctions to achieve its objective, even though there are other ways to achieve the objective that are less infringing. Although the criminal penalties originally proposed by the bill have been changed to administrative penalties, the same is true of the attempt to change behavior with the threat of sanctions. Legal sanctions for refusal to cooperate with epidemiological studies or hospitalization recommendations may encourage discrimination and prejudice against patients. Contrary to the government’s intention to bring social order, it may cause social unrest.

5 Mechanisms for Correcting Legal Norms

Let us take a closer look at mechanisms for correcting socially undesirable legal norms. When people have different preferences or beliefs regarding a given issue, and when governments or others attempt to change people’s behavior by introducing a uniform legal norm or standard, people may not accept that norm or standard. It may not be in line with reality, for example, or there may be high costs relative to the benefits of following it. In such cases, if there is room for market mechanisms to work, market segmentation may occur, and in equilibrium, the norm or standard may be accepted only by certain groups (Berg and Kim 2014; Berg, El-Komi, and Kim 2016).[54] Alternatively, even in the absence of a market mechanism, people may ignore the uniform legal norm or standard as time passes (Azar 2004). When the law imposes sanctions on violators and people cannot invalidate the legal norm simply by ignoring the law, they may initiate protest actions (Carbonara, Parisi, and Wangenheim 2012).

With respect to the COVID-19 legal policy on freedom of movement and business, the market mechanism cannot correct legal norms because there is no market. Another possible corrective mechanism is for people to oppose the legal norms themselves and invalidate them, but this would cause social friction among people with different norms. If some groups accept the legal norms and others do not in equilibrium and the equilibrium can be maintained peacefully, there may be fewer problems. However, since many COVID-19 legal policies require the cooperation of all citizens, social conflicts may arise among groups with different beliefs.

Another critical problem is that even if someone thinks a legal norm is inappropriate, it is difficult to speak out against it. Opposition to a particular legal policy is not always considered a deviation from the social norm. Criticism of problems in corporate or tax law is not considered non-compliance with social norms. In regard to COVID-19 laws, however, there is an atmosphere of intolerance toward expressions of dissent because of government propaganda that the law is correct and that compliance with the legal norms is in line with social justice. Therefore, any expression of opposition to COVID-19-related laws may be perceived as a deviation from the dominant social norm.

Normally, one deviation from social norms is not stigmatized unless the act is very serious, but repeated deviations from social norms can lead to severe stigmatization of the deviating party as a social nonconformist. In such cases, people may deviate from the social norm once but be hesitant to do so again (Kim and Lee 2001). As regards COVID-19 legal policies, there are many legal rules that restrict a variety of freedoms, such as freedom of movement, freedom to operate, and freedom to make decisions regarding vaccination. These legal policies interfere with individuals through the expressive effect of the law and have a coercive effect through the peer pressure effect, even if they do not involve legal sanctions or obligations. It is difficult for many people to publicly voice their opposition to all of these legal policies. Based on their social relationships at work or school, they risk being labeled by society as socially non-conforming, even if the legal norms are wrong.

Changing a legal norm requires a certain percentage of people to oppose it, but the cost of opposition is high for many people, and it takes time to overturn the legal norm, causing much social friction in the process.

6 Conclusions and Discussion

We used Japan’s COVID-19 laws as a case study to examine the effects on society of laws that introduce legal norms different from pre-existing social norms. The main lessons are as follows.

First, concerning restrictions on the movement of people, the government introduced rules that did not involve legal sanctions, and the expressive effect changed people’s behavior to some extent. However, the repeated issuance of emergency declarations reduced the expressive effect. Second, regarding the reduction of business hours, the government introduced rules with legal sanctions, and many businesses followed the legal norms. However, as a result of the repeated emergency declarations, non-compliant businesses began to appear, and some businesses protested by filing lawsuits. Third, the rule of imposing legal sanctions on infected people who refuse hospitalization measures has so far not manifested as a social problem, due to an insufficient supply of hospital beds, but many associate the current COVID-19 laws with the forced isolation of leprosy patients in the past and fear that it may encourage discrimination against infected people, their family, and health care workers.

As it became clear that the government’s COVID-19 policy did not fundamentally solve the problem of infection, people began to question the validity of the policy, and the number of people who did not support legal norms may have increased. In addition, while there were people who broke away from the legal norms, there emerged also those such as the self-restraint police who attempted to promote the legal norms to the extreme, and social conflicts became apparent.

The analysis in this paper also has implications for immunity or vaccine passport policies, which some countries have already introduced. Vaccine passport policies aim to encourage vaccination by restricting the right of the unvaccinated to use stores and public facilities. Some scholars have pointed out flaws in these policies (Kofler and Baylis 2020), which have already caused massive opposition demonstrations in many countries, leading to social conflicts both among citizens and between the citizens and the state (Dada et al. 2021). Japan has introduced a vaccine passport that only functions to prove vaccination but has not yet introduced a law that restricts the rights of unvaccinated persons. However, although it does not impose any obligation on the public, the government does apply the Preventive Vaccination Act to COVID-19 vaccines and recommends vaccination.[55] This policy, which relies on the expressive effect of the law to promote vaccination, has resulted in an increasing number of cases of unvaccinated people facing discrimination in the workplace and schools. In response, several local governments have enacted ordinances prohibiting discrimination against unvaccinated people (San-in Chuo Shimpo 2021).[56]

The lesson from the Japanese case is that laws do not work if they try to force legal norms that differ from pre-existing social norms in situations where there is no sufficient scientific basis for legislative facts or trust in policy or government. Japan’s experience proves that even when laws have only expressive effects without legal sanctions, they can divide social norms and lead to unnecessary social conflicts among people with different beliefs. In assessing the costs and benefits of a legal policy on COVID-19, it is necessary to consider the costs of such fragmentation of social norms and the emergence of social conflicts. Many governments currently underestimate this cost.

Corresponding author: Masaki Iwasaki, Seoul National University School of Law, Seoul, The Republic of Korea, E-mail:

Funding source: Seoul National University


The author thanks Shozo Ota and the participants at the 2021 Asian Law and Society Association’s annual conference.

  1. Research funding: This article was funded by the 2022 Research Fund of the Seoul National University Asia-Pacific Law Institute, donated by the Seoul National University Law Foundation.

  2. Conflicts of interest: The author has no conflicts of interest to disclose.


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Published Online: 2022-04-18

© 2022 Masaki Iwasaki, published by De Gruyter, Berlin/Boston

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