Während in den vergangenen Jahren die Forschung zum politisch rechtsorientierten und religiös-islamistischen Extremismus zunahm, blieb eine ähnliche Entwicklung beim Linksextremismus aus. Die vorliegende Studie untersucht spezifische Risiko- und Schutzfaktoren des Linksextremismus. Die Daten stammen aus einer Onlinebefragung mit 144 potentiellen Linksextremen, die wir mittels eines Online-Fragebogens u. a. über einschlägige linksaffine und -extreme Gruppierungen rekrutierten. Wir konzentrierten uns in unserer Studie auf aggressives und gewalttätiges Verhalten (nicht nur auf Einstellungen). 51 % unserer Teilnehmer waren männlich, das Durchschnittsalter war M = 26.74 (SD = 6.11). 92 Teilnehmer berichteten, politisch motivierte Gewalt gegen Personen und/oder Sachen begangen zu haben. Erhoben wurden theoretisch fundierte Einflussfaktoren der Person und des sozialen Umfelds. Eine hierarchische Regression konnte circa 50 % der Varianz der Gewalttätigkeit aufklären. Die Integration in ein gewaltbereites extremistisches Netzwerk hing deutlich mit der Durchführung extremistisch motivierter Gewalt zusammen. Eine persönliche kriminelle Vorgeschichte ging ebenfalls mit mehr politischer Gewalt einher. Wahrnehmungen von prozeduraler Gerechtigkeit und Legitimität konnten als Schutzfaktoren identifiziert werden. In einer explorativen Diskriminanzanalyse untersuchten wir Unterschiede zwischen Personen, die »nur« Gewalt gegen Sachen ausgeübt hatten, und jenen, die auch Gewalt gegen Personen berichteten. Gewaltorientierte extremistische Einstellungen waren der wichtigste Aspekt bei der Vorhersage der Gruppenzugehörigkeit. Die Ergebnisse werden theoretisch eingeordnet sowie Stärken und Schwächen der Studie diskutiert. Mehr empirische Untersuchungen zum Linksextremismus sind nötig, insbesondere solche mit einem längsschnittlichen Design.
While research on right-wing and religious-islamist motivated extremism has increased in recent years, the same is not the case for left-wing extremism. This study examines specific risk and protective factors of left-wing extremism. Using an online questionnaire, we studied a sample of 144 potential extremists, which we recruited via left leaning and extremist left-wing groups. The focus in our study was on aggressive and violent behavior (not only on attitudes). 51 % of our participants were male with a mean age of M = 26.74 (SD = 6.11). 92 had engaged in politically motivated violence towards property and/or persons. We examined theoretically relevant constructs on the individual level and in the social environment. A hierarchical regression analysis »explained« about 50 % of the variance regarding politically motivated violence. Positive integration into a violent extremist social environment was related to politically motivated violence. A personal criminal history predicted engagement as well. Perceptions of procedural justice and legitimacy were identified as a protective factor. In an exploratory discriminant analysis, we also examined differences between those who were »only« involved in violence towards objects (others’ property) and those who were also involved in violence towards persons. Positive attitudes towards the use of extremist violence were important in predicting group membership. The results are considered in light of current research and strengths as well as limitations are discussed. More empirical research on left-wing extremism is necessary, especially studies using longitudinal designs.
1.1 Phenomena and terminology
Radical attitudes and extremist actions are undermining free and democratic societies worldwide (Abay Gaspar et al. 2020). In response to these global challenges, research and preventive measures to counteract these trends have significantly increased (Bellasio et al. 2018; Mastroe & Szmania 2016). For left-wing extremism, however, this is much less the case compared to right-wing and Islamist extremism (Neu 2012; Treskow & Baier 2020). Left-wing extremism was particularly under scrutiny during the 1970s and 80 s (Pfahl-Traughber 2014). At this time typical examples were the Red Army Faction (RAF) – in the beginning also known as the Baader-Meinhof Gang – in Germany and partially related to it the Black September Organization in the Middle East, well-known for the attack during the Munich Olympics in 1972 (Gutmann 2008; Silke & Filippidou 2020; Wunschik 2007). However, public attention and research on current forms of left-wing extremism are much lower than on right-wing or Islamist extremism (e.g.; Campion 2020). For example, of 54 studies in a meta-analysis on risk factors none addressed left-wing extremism specifically (Wolfowicz et al. 2020). This stands in contrast to the increasing prevalence of politically motivated violence committed by left-wing extremists worldwide in recent years (Bundesministerium des Innern 2020; Europol 2020; Sarangi & Alison 2005; van Ham et al. 2018). For example, the Terrorism Situation and Trend Report by the European Union shows an increase in left-wing terrorist attacks from 2018 to 2019 in the EU, especially in Greece, Italy, and Spain (Europol 2020).
In Germany, most recent severe violent attacks have been carried out by right-wing terrorists (e.g., the National Socialistic Underground with ten deaths between 2000 and 2007) or Islamist terrorists (e.g., at the Christmas market in Berlin in 2016 with twelve deaths). However, many perilous violent attacks are also due to left-wing extremists. While left-wing extremist offenses were less prominent during the early 2000 s ranging from less than 1,500 to about 2,000 acts committed, a clear increase can be seen during the last two decades: The current report of the German Federal Office for the Protection of The Constitution (Verfassungsschutz), which monitors extremist actions, has registered 6,449 extremist offenses committed by left-wing extremists in 2019 (Bundesministerium des Innern 2020; Verfassungsschutzberichte 2021). About 1,000 were registered as politically motivated violence, which is an equally high number as violence committed by right-wing extremist. The overall number of 33,500 potential left-wing extremists is similar to that of right-wing extremists as well (Bundesministerium des Innern 2020). Of course, such statistics are often prone to judgement errors, follow internal guidelines, or do not reflect all relevant actions and, therefore, leave an unknown dark figure (e.g., Treskow & Baier 2020). Additional scientific research is therefore indicated to map left-wing extremism more effectively, but this is not a specific problem of this form of extremism.
The »modern« forms of left-wing motivated violence are similar to what the Violence Commission of the German Federal Government addressed as politically motivated violence in the 1980s (e.g., »autonomous« squatters and aggressive protesters against nuclear power and airport expansions; Lösel et al. 1990). Typical examples of left-wing motivated violence are arson attacks or other acts of violence against property of governmental institutions, private enterprises, as well as (alleged) right-wing extremists (Bundesministerium des Innern 2020; Europol 2020; van Ham et al. 2018). Left-wing motivated violence is also directed against (alleged) right-wing extremists and often manifests in massive violence against the police considered as representatives of a repressive state by supporters of the so-called Antifa (Antifascist Action), and other left-wing extremists. A recent example of such severe mass violence could be seen during the G20 Summit 2017 at Hamburg where national and international left-wing extremists came together for violent protest (Bundesministerium des Innern 2020; Siewert 2018; van Hüllen 2013).
Generally, various forms of radicalization, extremism and terrorism cannot be pressed in clear-cut definitions as some forms may partially overlap (e.g., faith-based and ethnically motivated forms) and can be heterogenous in themselves (Lösel et al. 2018). This is also reflected in the debate concerning definitions of left-wing extremism. The heterogeneity of the subcultures and groups in this field make defining left-wing extremism a challenging task with some groups striving for a communist society and others for anarchism (see for example Lehmann & Jukschat 2019; Schröder et al. 2020; Pfahl-Traughber 2020). Sometimes »left-wing militancy« is used instead of extremism to put a stronger emphasis on problematic actions (e.g., Bundesfachstelle Linke Militanz 2018; Gmeiner & Micus 2018; Treskow & Baier 2020). Treskow and Baier (2020) note that left-wing extremism comprises both attitudes as well as behavior. Overall, there seem to be certain overarching aspects that can be considered as relevant for left-wing extremism. Often, left-wing extremism encompasses opposition to free and democratic social orders, willingness to use violence and aims to build societies without classes or rulers. Typical topics in left-wing extremist groups are the fight against capitalism and fascism, as well as the fight for equal wealth distribution (Doosje et al. 2016; Pfahl-Traughber 2014; Treskow & Baier 2020). In regard to this definition, it is especially important to avoid conflating left-wing extremism with non-extremist forms of (left-wing) activism (Goede et al. 2020; Koehler 2021; Schröder et al. 2020). For example, anti-fascist positions are shared by many democrats. In left-wing extremism such positions are often connected with a willingness to use violence. Furthermore, current topics such as the fight against climate change are often used to recruit new members (Pfahl-Traughber 2020; Schroeder & Deutz-Schroeder 2015). However, not all individuals who have left-wing extremist attitudes turn to violence. This leads to the questions why people become radicalized to the point of using politically motivated violence but also what helps them to desist from extremist violence.
1.2 Development, risk, and protective factors
Various stages have been proposed describing the processes and mechanisms towards radicalization. Often, a cognitive sensitivity towards extremist ideas stands at the beginning (Dalgaard-Nielsen 2010; Moghaddam 2005; Wiktorowicz 2005). Although general and linear developments into extremist violence are rightly challenged in the literature, recent research on risk factors has given insights into specific factors contributing to pathways towards radicalization. As in general research on violence (e.g., Lösel & Bender 2017), these factors can be found on the macro (societal) level, the meso (group) level, and the micro (individual) level (Doosje et al. 2016; McCauley & Moskalenko 2008; Schmid 2013). These levels are not linear but influence each other: for example, individuals might seek out certain groups due to their individual motivations and attitudes; conversely groups actively recruit individuals and provide violence legitimating views (McCauley & Moskalenko 2017; Webber & Kruglanski 2018). Identifying lists of replicated risk factors may not contain a sound explanation of the complex phenomenon of extremism. Instead, one needs to distinguish between risk markers (e.g., gender) and causal factors of radicalization (Schils & Pauwels 2016; Wikström & Bouhana 2017). Furthermore, risk factor approaches do not explain why many people do not turn to violence despite enhanced risks in their lives (Lösel & Farrington 2012; Moghaddam 2005). Doosje et al. (2016), for example, proposed shields of resistance that help individuals from further spiralling towards violent extremism. Knowledge on such protective factors can be used to enrich tools of radicalization risk assessment and help to develop successful prevention programs (Lösel 2021). While some protective factors have a direct protective effect regardless of other influencing factors, other protective factors buffer effects in the presence of risk factors. Buffering factors can be analyzed via regression analyses or – in a more person-oriented approach – by examining high risk groups with a deviant versus non-deviant behavioral outcome (Lösel & Bender 2003, 2017; Ttofi et al. 2016).
So far, research on risk and protective factors has shown that male gender and younger age, for example, are often associated with engagement in violent extremism (e.g., Jensen et al. 2016), although female participation seems to play a bigger role in left-wing extremism compared to other forms of extremism (Carson 2017; Cunningham 2007; Jugl, Bender & Lösel 2021). Yet, such background characteristics are generally no strong predictors of radicalization (e.g., Wolfowicz et al. 2020) and provide little explanation on the reasons for radicalizing.
In contrast, aspects of the social environment and social integration seem to play a more important role (Baier, Manzoni & Bergmann 2016; Dalgaard-Nielsen 2010). Exposure to extremist networks was found to be an important predictor of violent extremism. For example, individuals exposed to extremist settings adopt radical views and attitudes legitimating the use of violence through social learning processes (Becker 2019; Jasko et al. 2017). Groupprocesses seem to be highly relevant for left-wing extremism, where violence is often committed in groups (Behrendes 2020). Protective factors, however, can be found in the social environment as well. Positive social integration into a free and democratic society seems to protect against radicalization, for example, via mechanisms of social control. Nurturing bonds established with families, peers, workplace, school, and civil organizations keep individuals from engaging in norm-deviating behavior (Baier et al. 2016; Hirschi 1969; Lösel et al. 2020; Pauwels & De Waele 2014).
Further control mechanisms are due to the individual’s relation to the wider state context. When individuals feel as though the state and its actors, especially the police, treat them just and fair, they may accept the legitimacy of the police as actors to enforce law and order (Tyler 2006). In turn, this seems to increase obedience to social norms and decrease the likelihood of engagement in violent extremist behavior (Lösel et al. 2018; Schils & Pauwels 2016; Tyler 2006). In contrast, perceived discrimination by governmental institutions can undermine such perceptions loosening the effect of control mechanisms. Discrimination in general or perceptions of unjust treatment of oneself as well as the group one belongs to have been reported to be precursors of violent extremism (Frounfelker et al. 2019; Pauwels & De Waele 2014). Discrimination can cause strains that lead individuals to adopt violent extremist attitudes, which are, in turn, related to extremist behavior and motivate individuals to participate in social movements and violent groups (Agnew 2001; Maskaliūnaitė 2015; Pauwels & De Waele 2014; Wolfowicz et al. 2020).
These strains and perceptions of injustice can lead to a loss of meaning in life, which has been identified as a precursor of extremist actions used to restore one’s significance within the framework of the significance quest theory (Kruglanski et al. 2009). In face of such strains, individuals might also feel pushed out of the society and experience political powerlessness. These are aspects of anomia, which are related to the adoption of violence legitimating views and deviating from normative behaviour in the society (Adam-Troian et al. 2020; Schils & Pauwels 2016). Srole (1956) as well as Middendorp and Meloen (1990) suggest that these feelings of anomia can also result in the adoption of authoritarian views. Authoritarianism includes beliefs favoring hierarchies, strict abidance of social norms in the own group, as well as legitimating the use of violence against those who are perceived to deviate from these social norms (Altemeyer 1996; Pauwels & De Waele 2014). These beliefs can lead the individual to the perception of a more secure world, offering a respite of feelings of anomia (Middendorp & Meloen 1990). Accordingly, authoritarianism was found to be an important predictor of extremism (Wolfowicz et al. 2020).
Obviously, these concepts fit particularly to right-wing, faith-based, and nationalist extremism. In the case of left-wing authoritarianism, the facets such as submission to authorities relate to the submission to revolutionary movements (van Hiel, Duriez & Kossowaska 2006). There is an ongoing debate, whether left-wing authoritarianism even does exist (Benjamin 2014). But while there seem to be some issues in detecting left-wing authoritarianism in moderate samples, people holding more extremist views tend to report such beliefs (Jugl et al. 2021; van Hiel 2012; van Hiel et al. 2006).
A personality-related aspect that might help protect individuals from engaging in violence despite certain beliefs and cognitions, is self-control which includes several dimensions such as impulsivity or thrill seeking (Gottfredson & Hirschi 1990; Lösel 1975, 2017). Within the framework of the Situational Action Theory (SAT) self-control is especially important if individuals are prone to use violence as a subjectively legitimate way to achieve their goals (Wikström 2006). High levels of self-control can prevent individuals from engaging in violent extremist actions while low self-control increases the risk of extremist behavior. In the context of violent extremism, especially the dimension of risk-seeking was found to be a significant predictor (Baier et al. 2016; Schils & Pauwels 2016). This is in correspondence with general research on criminal behavior in which low self-control is related to more criminal activity (Lösel & Farrington 2012; Vazsony, Mikuška & Kelley 2017). Criminal history, in turn is also related to a greater likelihood of violent extremism (Wolfowicz et al. 2020).
1.3 Concept and hypotheses of the present study
The above-mentioned theoretical concepts and empirical findings give some insights into potential mechanisms of radicalization towards violent extremism as well as factors protecting against extremist violence. However, specific research on left-wing extremism is still rare (Lösel et al. 2020; Wolfowicz et al. 2020). Often, analyses of left-wing motivated violence are based on crime data drawn from official reports (Bundesministerium des Innern 2020; Europol 2020; Jensen et al. 2016; Krumm 2015). This approach is insofar limited as problems in judgment of extremist motivations and dark figures remain (Treskow & Baier 2020). Furthermore, these analyses are often limited to demographic (background) characteristics. Some studies on left-wing extremism tried to counter these problems by approaching youths in schools and other settings and administering questionnaires (e.g., Pauwels & Svensson 2017; Treskow & Baier 2020). Although this helps to shed some light onto left-wing radicalization, the prevalence of extremist violence in samples of the general population is very low (Sarma 2017). Therefore, our study aimed to approach more specific left-wing oriented extremist individuals in a focussed approach. While Jugl et al. (2021) looked at factors leading to left-wing extremist attitudes, in this study we focus on potential left-wing extremists (i.e., individuals with a more left-wing extremist prone world view as described below) as a high risk group of violent and non-violent extremists. The main research question is to get insights on why some radical individuals (i.e., individuals with left-wing extremist world views) turn to violence and others do not. Furthermore, we wanted to delve deeper into what leads individuals to commit different types of violence. Left-wing extremist violence often contains damage of property (violence towards objects), however, a considerable amount targets persons as well (Mletzko 2010; Treskow & Baier 2020). There is a long-lasting debate about the differentiation between violence against persons and objects (e.g., Lösel et al. 1990). In basic research on aggression, the intended harm of others is a key criterion. Violence refers to physical attacks or similarly serious action (e.g., threat). Violence against property contains an indirect harm of others, but also indicates a partially less serious »quality« in comparison to violence against persons. Therefore, we examined both groups of violent extremists more closely in an exploratory discriminant analysis. For our empirical operationalization of politically motivated violence see Table 1 in the method section.
According to the above-mentioned theories and findings, we differentiate between individual and context factors. On the individual level, we expect that attitudes and cognitions such as perceived discrimination, anomia, left-wing authoritarianism, violent extremist attitudes legitimating the use of violence for political reasons, as well as a lack of meaning in life may increase the likelihood of violent extremism (Adam-Troian et al. 2020; Borum 2011; Schils & Pauwels 2016; Wolfowicz et al. 2020). In contrast, positive perceptions of procedural justice and police legitimacy should predict abstaining or desistance from extremist violence. High self-control as a personality-related variable should also act as a protective factor (Lösel et al. 2020). On a societal level, we expect factors of the social environment and the individual’s integration to be related with the likelihood to commit left-wing politically motivated violence (Lösel et al. 2020; Manzoni et al. 2018; Schils & Pauwels 2016; Wolfowicz et al. 2020).
2.1 Recruitment and sample description
Between April and December 2019, we carried out an online survey and shared the link to our questionnaire with around 700 different groups and contacts. We distributed the link in online groups and forums on far-left political subjects, among personal contacts as well as left-wing oriented political parties and student groups in Germany. A special approach of our study consisted of reaching out to groups recognized by the German Verfassungsschutz as left-wing extremist actors (Bundesministerium des Innern 2019) to increase the chances of including radicalized individuals supporting left-wing extremist world views in our survey. We searched the websites and social media profiles of such actors for contact details and contacted them via email or private messages. Using a snow-balling method, we asked them to distribute our survey among their social contacts. Of course, due to this procedure, we cannot say how many people received our invitation in total since we have no insights on how and whether the link was shared beyond the initial contacts.
We concentrated on individuals between 16 to 40, since this seems to be an age range where extremist action is most likely to happen (Jensen et al. 2016; Pfahl-Traughber 2014). All participants were informed about the data protection regulations according to the researchers’ institutional guidelines. Despite these guarantees some contacts told us that they would not participate out of fear of consequences from state authorities. From those who did proceed with the questionnaire, informed consent was obtained. In total, from 424 persons starting the questionnaire, 252 participants (59 %) finished the survey.
We split our sample into a high risk versus low-risk group. Members of the low risk group (n = 108) showed lower support of left-wing extremist world views while individuals in the high risk group reported more left-wing extremist attitudes. The sample split is further described under the section Measurement of variables. This split allowed us to analyze those who are more likely to be extremists due to their world views and compare among this group non-violent with violent actors. Using this splitting procedure, we identified 144 potential extremists with left-wing extremist world views of which 63 were female, 73 male, and eight identified as other/non-binary. As participants were asked to report their biological gender, eight non-binary individuals seem like a high rate. Generally, left-wing extremist group provide a framework of egalitarianism and anti-sexism (Koehler 2021) which might be more attractive for females as well as individuals with a diverse gender identity in contrast to other extremist movements. Of course, we cannot rule out that individuals who are biologically male or female but identify differently chose the other/non-binary category to express themselves. Additional analyses indicated no bias in our analysis when including these individuals, suggesting that this category was not misused. The participants mainly held a German citizenship (94 %) and lived in West-Germany including the city of Berlin (79 %). 59 % of the participants lived in a large city with more than 100.000 inhabitants. Our targeted sample included both non-violent and violent potential left-wing extremists. In total, 92 participants (64 %) admitted to having committed politically motivated violence at least once. This is a much larger proportion as in general community samples. For example, in studies on general forms of extremism but also left-wing extremism reported extremist violence often lies below 10 % (e.g., Baier et al. 2016; Baier & Pfeiffer 2011; Pauwels et al. 2014, Pauwels & De Waele 2014). This validates our focussed approach (although we do not have comparative data for those who declined participation).
2.2 Measurement of variables
2.2.1 Politically motivated violence
We used the items by Pauwels and De Waele (2014) and added some illustrative examples from Baier et al. (2016) to measure whether individuals had committed politically motivated violence at any given time. The scale by Pauwels and De Waele (2014) considers both violence oriented towards property as well as persons. Often, left-wing extremists distinguish between violence towards property and towards persons in their legitimization of violence. Violence towards persons is generally less approved, however, violence against those who are seen as the enemy is more readily accepted (Van Hüllen 2013). Sometimes, left-wing violence especially directed towards persons is mainly assessed by asking whether individuals have used violence against right-wingers (e.g., Baier et al. 2016; Schröder et al. 2020). This, however, limits left-wing politically motivated violence to one specific aspect, namely anti-fascism. Even when considering the special dynamics of conflict escalation during protests between left-wing extremists and the police (Gmeiner & Micus 2018), the police and other state authorities as well as representatives of capitalism are seen as enemies and are potentially at risk of experiencing left-wing extremist violence (e.g., Pfahl-Traughber 2020).
In total, ten items were used as presented in Table 1. In contrast to the categorization in Pauwels and De Waele (2014), however, we subsumed violence against government officials/the police under person-oriented violence instead of violence towards property. Participants were presented with the list of items and asked whether they had never, once, two-/three times, or four times/more often committed any of these acts out of political motivation (Pauwels & Svensson 2017). For our analysis, we dichotomized the highly skewed scale so that our outcome variable expressed whether individuals had never committed politically motivated violence (coded as 0) or had at least once committed politically motivated violence (coded as 1).
|Violence against objects/others’ property|
|...painted or sprayed a political message or symbol on a wall?|
|...participated in illegal activities (e.g., occupying a house or factory)?|
|...destroyed something (e.g., breaking windows)?|
|...damaged the property of others (e.g., throwing bags of paint on houses)?|
|...set fire to something (e.g., car, house)?|
|Violence against persons|
|...used violence against government officials (e.g., throwing bottles/stones at the police)?|
|...hit or injured someone?|
|...threatened someone on the internet?|
|...threatened someone on the streets?|
|...hit a foreigner?|
Note. Participants were asked if they had ever committed any of the mentioned acts never, once, two-/three times, four/more times due to their political motivation.
2.2.2 Sample split: Left-wing extremist attitudes and potential extremists
Our analyses in this article concentrated on high risk individuals, i.e. individuals who supported left-wing extremist world views. The scale measuring left-wing extremist world views/attitudes for splitting our sample into potential left-wing extremists (high risk group) and others (low risk group) was derived from Schroeder and Deutz-Schroeder (2015). It encompassed 14 items which were rated on a Likert scale from 1 (do not agree at all) to 5 (totally agree). These items measured four dimensions of a left-wing extremist world view including anti-capitalism/-fascism, anti-racism, anti-democratic views, communist ideology/historical conception. To avoid conflating legal and extremist views (Koehler 2021), the composite score of the different dimensions formed the basis for assessing left-wing extremist world views: The more support someone shows for the items, the more extreme is the world view considered to be. The scale had very good internal consistency in our sample including both high and low risk individuals (Cronbach’s α = .92). Schroeder and Deutz-Schroeder (2015) suggest dichotomizing the scale along the arithmetic mean to identify those scoring high on extremism as potential extremists due to their high acceptance of left-wing extremist world views. The authors rightly note that there is no widely accepted definition when someone can be considered as left-wing extremists. Such cut-offs are, therefore, often arbitrary (Schroeder & Deutz-Schroeder 2015). Although this is a general problem of extremism research, we still followed this recommendation for our analyses and also split our sample along the arithmetic mean to facilitate better possibilities for comparison in the research field. While the groups did not differ regarding gender and age, potential extremists were significantly more likely to report involvement in politically motivated violence (92 vs 23 reports of politically motivated violence; Chi² (1, N = 252) = 45.13, p < .001) supporting our group formation. They also differed significantly on most individual and context variables despite anomia, meaning in life, and social integration. The high risk group always reported more negative perceptions as well as more extremist attitudes, cognitions, and social surroundings.
2.2.3 Attitudes, cognitions, and personality factors
We measured perceived discrimination with eight items derived from (Schils & Pauwels 2016). The scale that showed very good internal consistency (Cronbach’s α = .91) entailed both perceptions of in-group discrimination and discrimination against oneself. Meaning in life was assessed with the German adaptation of Meaning in Life Questionnaire (Steger et al. 2006; The Meaning in Life Questionnaire 2020). The five-item scale showed very good internal consistency (Cronbach’s α = .92). Left-wing authoritarianism measured with eight items (van Hiel et al. 2006) showed acceptable internal consistency (Cronbach’s α = .79) in our sample. Anomia was assessed with an eight-item scale by Fuchs (2003) and had an acceptable Cronbach’s α of .70. The four-item scale by Ribeaud, Eisner & Nivette (2017) to assess violent extremist attitudes showed good internal consistency (Cronbach’s α = .89). The perception of procedural justice was measured with three items and police legitimacy with seven items (European Social Survey 2010; Jackson et al. 2012; Pauwels & De Waele 2014). Both scales had good internal consistencies in our sample (Cronbach’s α = .81; Cronbach’s α = .85). Furthermore, we measured self-control with four items (Grasmick et al. 1993; Seipel 2014) and found good internal consistency in our sample (Cronbach’s α =.87). General criminal history was assessed by asking whether individuals had ever committed an offense independently of their politically motivated action. Means and standard deviations of our sample on the different scales are presented in Table 2 in the results section (see Descriptive data).
2.2.4 Social environment/integration
For assessing the social environment, we asked participants whether close others (i.e., family, friends, peers) had been involved in politically motivated violence. We checked whether individuals were more embedded in a left- or right-leaning social environment. To do so, we adapted the one-item left-right self-placement scale (Caprara & Vecchione 2018; Rico & Jennings 2016). Participants were asked to indicate where on the scale they would locate people close to them. Lower values indicated that participants reported a more left-leaning social environment. Furthermore, we measured perceived social integration with a subscale from the German Social Support Questionnaire (Fydrich et al. 1999; Fydrich et al. 2009). The scale consisting of seven items showed good internal consistency in our sample of potential extremists (Cronbach’s α = .82).
2.3 Statistical analysis
To test our hypotheses, we analyzed the data in a hierarchical logistic regression in IBM SPSS Statistics Version 26. We first entered attitudes, cognitions, and other personality-related variables. This was followed by variables of social environment and integration. We chose to follow this sequence of entry, although the other way would also have been plausible. Research on radicalization is lacking longitudinal designs and causal directions are difficult to deduce (Batzdorfer & Steinmetz 2020). While individuals with certain mind-sets might seek out specific groups, group processes also reinforce individual perceptions and attitudes (e.g.; Batzdorfer & Steinmetz 2020; Webber & Kruglanski 2018; Wikström & Bouhana 2017). This bidirectional relation is similar to the general process of affiliation with delinquent groups (e.g., Bender & Lösel 1997). To avoid a bias, we also changed the direction of entry in our hierarchical regression model, but found no substantial differences.
In an exploratory discriminant analysis, we also examined which risk and protective factors distinguished between those individuals involved in violence towards objects and those who were also involved in violence towards persons.
3.1 Descriptive data
Of 144 potential left-wing extremists 92 reported to have been engaged in politically motivated violence at least once. This indicated a rate of 64 % violent extremists with a left-wing extremist world view in our high risk sample. 24 % (n = 35) had engaged in violence towards persons at least once, while 63 % (n = 90) reported violence towards property at least once. Nearly all individuals involved in violence towards persons (n = 33) had also committed violence towards property.
The most frequent forms of violence towards property included participation in illegal activities such as house occupation/squatting (n = 66) as well as painting/spraying political symbols or messages on walls (n = 63). About one third admitted to destroying something (n = 38) or damaging someone’s property (n = 47). Eight participants reported they had already ignited something due to their political motivations. Regarding violence directed toward persons, using violence against state officials such as police officers was reported by 22 participants. Twenty participants stated that they had hit someone at least once and 18 reported to have threatened someone on the streets. Three people reported to have threatened someone online. Hitting a foreigner was only mentioned once.
People reporting violence were with an average of M = 27.88 (SD = 6.06) significantly older than those not involved in violence (M = 24.73; SD = 5.73; t(142) = -3.06, p < .01) but did not differ regarding gender. Male violent extremists, however, reported significantly more person-oriented violence. 27 males had committed person-oriented violence at least once, seven females, and one non-binary individual admitted to engagement in such violence. Non-binary individuals did not differ from males and females in any kind, but the group was small. Violent extremists reported significantly more general criminal history (65 vs. 14 times; Chi² (1, N = 144) = 25.65, p < .001) as well as politically motivated violence by close others (60 vs. 14 times; Chi² (1, N = 144) = 19.50, p < .001) than non-violent extremists.
Taking a closer look at the intercorrelations between politically motivated violence and individual as well as environment-related factors, we mostly found expected, but also some unexpected results (see Table 2). Good social integration was related to committing politically motivated violence. Despite theoretical expectations, neither feelings of anomia, lack of meaning in life, discrimination and left-wing authoritarian attitudes were related to politically motivated violence. Some high correlations emerged between the variables. For example, perceived legitimacy and procedural justice were highly correlated; so were left-wing authoritarianism and violent extremist attitudes. Social integration was closely related to meaning in life and lower levels of self-control went along with non-extremist criminal history. As legitimacy and procedural justice both relate to perceptions of integrity and fairness of the government and its actors (Tyler 2006) and were highly correlated in our study (r = .78, p < .001), we decided to combine both scales for further analysis to avoid problems of multicollinearity.
|1. Politically motivated violence||- - -|
|2. Criminal historya||.42***||- - -|
|3. Politically motivated violence by othersb||.37***||.29***||- - -|
|4. Political orientation of others||-.31***||-.15||-.28**||- - -||4.46 (1.48)|
|5. Perceived social integration||.28**||.16||.21*||-.31***||- - -||3.78 (0.75)|
|6. Violent extremist attitudes||.29***||.33***||.27**||-.24**||.13||- - -||2.74 (1.10)|
|7. Procedural justice||-.45***||-.31***||-.28**||.19*||-.10||-.45***||- - -||2.25 (0.80)|
|8. Perceived legitimacy||-.36***||-.23**||-.28**||.39***||-.09||-.47***||.78***||- - -||2.27 (0.76)|
|9. Left-wing authoritarianism||.13||.14||.05||-.13||-.01||.63***||-.35***||-.37***||- - -||2.34 (0.70)|
|10. Anomia||-.04||.09||-.04||-.30***||-.19*||.02||.03||.10||.13||- - -||1.49 (0.25)|
|11. Meaning in life||.09||-.01||.07||-.08||.52***||.04||-.08||-.05||.05||-.20*||- - -||4.48 (1.59)|
|12. Discrimination||.13||.07||-.01||-.09||-.12||.10||-.19*||-.20*||.27**||.08||-.24**||- - -||2.29 (0.88)|
|13. Self-control||-.34***||-.44***||-.23**||.15||-.00||-.28**||.38***||.33***||-.23**||-.08||-.02||-.07||- - -||3.44 (1.00)|
3.2 Regression analysis on politically motivated violence
We decided against including all independent variables in our model to avoid overfitting our analysis. However, we also tested the model including non-significant variables as well but no improvements to the model were detected. As can be seen in Table 3 our model fit for our hierarchical regression on politically motivated violence increased significantly with each step. Nagelkerke’s R² of .47 in the last step indicates a good fit of our model. We found that participants who had also committed general offenses independent of their political motivation were more likely to engage in politically motivated violence (Exp(B) = 3.40, CI95 % [1.33, 8.68]). On the individual level, positive perceptions of procedural justice and legitimacy protected against involvement in politically motivated violence (Exp(B) = 0.49, CI95 % [0.28, 0.85]). Regarding aspects of social environment/integration, positive social integration was related to more politically motivated individual violence (Exp(B) = 1.99, CI95 % [1.06, 3.74]). With a p-value of .053 and a large effect size of Exp(B) = 2.39 (CI95 % [0.99, 5.77]) having close others in the social environment who have committed extremist violence seems to play a role for own involvement as well.
|Predictors||Criterion variablePolitically motivated violence|
|Model 1||Model 2|
|B (SE)||Exp(B)||B (SE)||Exp(B)|
|Constant||0.64 (1.11)||1.90||-0.67 (1.83)||0.51|
|Attitudes, cognitions, and personality factors|
|Criminal history||1.41 (0.45)||4.09**||1.23 (0.48)||3.40*|
|Perceptions of procedural justice and legitimacy||-0.81 (0.27)||0.45**||-0.72 (0.29)||0.49*|
|Violent extremist attitudes||0.10 (0.22)||1.11||0.01 (0.24)||1.01|
|Self-control||-0.26 (0.24)||0.77||-0.38 (0.27)||0.69|
|Perceived social integration||0.69 (0.32)||1.99*|
|Political orientation of others||-0.20 (0.16)||0.82|
|Politically motivated violence by othersa||0.87 (0.45)||2.39†|
3.3 Discriminant analysis of different perpetrators of politically motivated violence
In our sample, 92 individuals had at least once engaged in politically motivated violence. While 57 had been involved in violence towards property, two individuals had committed violence towards persons only and 33 had engaged in both forms. For the discriminant analysis, we compared those involved in violence towards property with the group who had targeted persons (and also property). We included variables into the presented model (see Table 4) that significantly correlated with the outcome in a bivariate analysis. The test of equality of group means showed that the groups differed significantly on the five included variables.
Our model discriminated better than by chance with λ = .81 (χ2 (5) = 18.99, p < .01). The canonical correlation of .44 indicates that the model accounted for 19 % of the variance between both groups. Overall, 71 % of our cases could be correctly classified. All variables loaded higher than .50 on the discriminant function as can be seen in the structure matrix (Table 4). Therefore, they contributed significantly to the discrimination of the groups. As indicated by the standardized canonical coefficients, some aspects were more important than others. The largest effect was found for violent extremist attitudes indicating that individuals involved in violence directed towards persons as well as property were more supportive of the use of violence for goal achievement. They were also more likely to report a personal criminal history and had fewer positive perceptions of procedural justice as well as legitimacy but reported more politically motivated violence by close others. Despite its smaller coefficient, left-wing authoritarianism was significantly more present among those also involved in violence towards persons.
|Variables||Standardized Canonical Coefficients||Structure matrix|
|Violent extremist attitudes||.43||.80|
|Criminal history a||.36||.55|
|Politically motivated violence by others||.30||.51|
|Perceptions of procedural justice and legitimacy||-.29||-.65|
a Dichotomous variable coded as 1 = yes, 0 = no/don’t know.
While research on right-wing and Islamist radicalization and extremism has risen immensely in the last years, fewer studies addressed left-wing extremism (Treskow & Baier 2020). Therefore, we recruited a high risk sample of potential left-wing extremist individuals with high support of left-wing extremist world views and analyzed which factors contributed to or prevented from engaging in politically motivated violence. To generate a relevant sample of potential extremists, we approached left-wing oriented as well as left-wing extremist individuals with an online questionnaire. We analysed data from 144 potential extremists of whom the majority (64 %) reported to have committed politically motivated violence. Violence towards property was reported more often than violence directed towards persons. This is in line with official data from governmental institutions and databases on violent extremism (Bundesministerium des Innern 2020; Carson 2017). In an exploratory discriminant analysis, we examined the differences between those who were »only« involved in violence towards property and those involved in person-oriented violence as well as both forms.
Regarding background characteristics, gender did not differ between violent extremists and others. This is in so far not too surprising, since there is a more equal distribution of male and female activists in left-wing extremist movements compared to right-wing groups (Carson 2017). In contrast to general findings in the field of extremism (Jensen et al. 2016; Wolfowicz et al. 2020), in our study on left-wing extremism older age was related to violence. This may suggest that left-wing extremists have a longer and consolidated history of radicalization than other extremists. However, it must be taken into account that our violence scale did not specify a certain time frame, so that older individuals could have had more opportunities to commit crime. While these demographic characteristics might help to describe the examined groups, they do not provide information on potential causal factors contributing to the engagement in violence (Schils & Pauwels 2016). For example, the huge majority of males or females in the society does not adhere at all to political extremism. Therefore, we examined aspects related to the social environment as well as cognitions and personality factors.
An individual’s criminal history seemed to play a role for politically motivated violence. This is in accordance with studies on general forms of extremism as well as left-wing extremism (e.g.; LaFree et al. 2018; Treskow & Baier 2020). It also corresponds to findings on general violence, where criminal history is a strong predictor for future crime (Yukhnenko, Blackwood & Fazel 2020). There is empirical support that general criminal behavior is well predicted by low self-control (Vazsonyi et al. 2017; for differentiations see Lösel 2017). Similarly, self-control was found in different contexts of extremism to protect against engaging in violent extremism (Becker 2019; Schils & Pauwels 2016; Treskow & Baier 2020). In contrast to our expectations, self-control did not significantly predict the outcome in the hierarchical regression. Nevertheless, the bivariate correlation analysis showed a relationship between engagement in violence and self-control. Considering the high correlation between criminal history and self-control, a suppressor effect in our model is likely. Indeed, testing the model without criminal history, self-control protected against politically motivated violence. As Batzdorfer and Steinmetz (2020) concluded, cross-sectional radicalization research deals with the problem that analyzed constructs are themselves often outcomes of other included constructs. This makes it difficult to discern which factors may have causal influence. Still, our findings indicate that certain criminal propensities and experiences of past crimes not related to extremism increase the risk of committing left-wing politically motivated violence.
We found that perceptions of procedural justice and legitimacy protected against involvement in violence. Within the procedural justice framework, perceptions of fair treatment by the government increases compliance with existing rules (Jackson et al. 2012; Schils & Pauwels 2016; Tyler 2006). Basic law abidance was also relevant in our systematic reviews and meta-analysis of protective factors against other forms of extremism (Lösel et al. 2018; Lösel et al. 2020). The police are one of the main »enemies« of left-wing extremist movements and violence often cumulates in confrontations during protests (Bundesministerium des Innern 2020; Siewert 2018). Therefore, transparent actions of police officers might be an important aspect to prevent individuals from engaging in politically motivated violence (see Jugl et al. 2021). Furthermore, more positive interactions between police and potential left-wing extremists could reduce tendencies of dehumanization. Dehumanization of enemies is a common practice to legitimate the use of violence (Giner-Sorolla, Leidner & Castano 2011; Gøtzsche-Astrup, van den Bos & Hogg 2020). Positive intergroup contact effectively decreases such tendencies and improves trust among groups (Bruneau et al. 2020; Capozza, Di Bernardo & Falvo 2017).
Somewhat surprisingly, we found less support for our remaining hypotheses on the individual level. Individual factors such as left-wing authoritarianism, discrimination, anomia, and meaning of life were not related to engagement in politically motivated violence. According to the SAT applied to the context of extremist violence feelings of discrimination can be considered as precursors for individuals to develop extremist propensities and become exposed to extremist settings (Schils & Pauwels 2016). A plausible explanation of our findings relates to the specific composition of our sample. We analyzed a sample of potential extremists at high risk, which would suggest that they have already proceeded along the path of radicalization. Therefore, factors which might be more important in the beginning of the radicalization process, would be less relevant in later stages. For example, while loss of meaning in life can activate the quest for significance, adopting extremist goals and sharing extremist group norms can restore meaning in life (Kruglanski et al. 2012). Engaging in violence, however, was not related to an enhanced sense of meaning in life but related to social integration (in the respective extremist group).
Accordingly, social integration showed no protective effect. A specific violence supporting environment could counteract positive effects of social integration into the mainstream society. For individuals already entrenched in radical ideas, mainstream activities, and integration into the mostly law-abiding general society might lose attractiveness and, therefore, lose its otherwise buffering protective effect (Lösel et al. 2018; Lösel et al. 2020). Overall, potential extremists who committed violence seemed to be well integrated into a violence prone setting. Our analysis also revealed a clear trend that engagement in politically motivated violence was more likely if close individuals in the environment had committed politically motivated violence.
In a review by Treskow and Baier (2020), three out of eight studies analyzing the relationship between violent peers and left-wing extremism identified the former as a risk factor. A social environment endorsing violence legitimating views or actively engaging in violence to reach political goals increases the risk of radicalization and turning to violence (Becker 2019; Schmid 2013). Shared ideology can make an individual more prone to using violence and contact with radical individuals can reinforce their behavior via processes of social learning and peer pressure (Bandura 1973; Bartlett, Birdwell & King 2010; Schils & Pauwels 2016; Webber & Kruglanski 2017). That left-wing extremists are often well integrated into their radical network makes disengagement difficult (Koehler 2021). To help deradicalization processes in individuals it is, therefore, necessary to help individuals rebuild networks within the mainstream society that equally offer positive integration and experiences. It is, therefore, an important, albeit difficult step to loosen the ties between left-wing extremists and their networks to prevent them from further engaging in violence.
Often, left-wing extremists state that they disapprove of violence towards persons. However, frequent targets of left-wing extremist violence, especially the police, are often dehumanized and violence towards them legitimized as violence towards the system (Gmeiner & Micus 2018; van Hüllen 2013). As Gmeiner and Micus (2018) state, violence towards property can be a precursor to more severe forms of violence targeted at persons. Our study offers valuable insights into the factors that contribute to committing different forms of politically motivated violence. While violent extremist attitudes made no significant contribution in the regression analysis, our discriminant analysis revealed that violent extremists who also engaged in violence towards persons reported higher acceptance of violence use for goal achievement. Furthermore, criminal history as well as politically motivated violence in the social environment were found more frequently in individuals who committed violence against persons and not only against objects. Similar mechanisms of reinforcement and social learning as described above might be relevant for the willingness to attack persons. Perceptions of procedural justice and legitimacy were again found to act in a preventive manner: Individuals engaged in violence towards property only showed higher perceptions in contrast to others. Additionally, while not as important as other factors, left-wing authoritarianism was more prevalent for those also attacking persons. To a certain degree, left-wing authoritarian views are related to violent extremist attitudes since the scale by van Hiel et al. (2006) includes the facet aggression and its acceptance in political movements. Therefore, support of violence legitimating views in general as well as support of violence for a specific cause (e.g., a revolutionary movement), seem to increase the likelihood to act out more strongly and commit more than just attacks against objects.
4.1 Limitations and strengths
Our recruitment and sample size did not allow an estimation on how representative the data are. However, this is an inevitable problem when investigating left-wing extremism. Research on violence and extremism is a sensitive topic and although individuals seem to be basically open to admit their delinquency in anonymous self-report measures (Babinski, Hartsough & Lambert 2001; Farrington et al. 2014; Thornberry & Krohn 2003), recruiting individuals from the left-wing extremist spectrum is particularly difficult and needs to overcome distrust (Schultens & Glaser 2013). We tried to do so by approaching them sensibly and guaranteeing anonymity. Still, we cannot be sure that participants disclosed all their actions. Besides under-reporting, effects of over-reporting might also have occurred. However, for assessing the outcome individuals did not state whether they had committed politically motivated violence or not but indicated how often they had engaged in such behavior. Excessive over-reporting would have probably been reflected in the answers showcasing very frequent engagement. Overall, this did not seem to be the case. Therefore, we assume that most individuals were willing to share information on their politically motivated actions correctly, and the high prevalence indicates that our sample recruitment was successful. This is a strength of our study. However, it should be kept in mind that politically motivated violence is a very sensitive topic in general and research benefits from multi-methodological approaches. The recruitment of our participants who already had an affinity to left-wing extremism may have reduced the variance in our data as compared to community samples with large majorities of non-extremists. Therefore, it is another strength that our hierarchical regression ›explained‹ about 50 % of the outcome variance.
Left-wing extremism is a highly controversial topic as reflected in the current (scientific) debate. The variety of aims, subgroups, and ideological fragments complicates clear cut definitions. Therefore, left-wing extremism is rather a collective term encompassing different aspects (Pfahl-Traughber 2020). This is not surprising, since other forms of extremism show similar challenges as well (e.g., Heller et al. 2020; Lösel et al. 2018). Besides these challenges, it can be assumed that left-wing extremism encompasses certain recurring aspects (e.g., Goede et al. 2020). Therefore, more studies are necessary to develop a tool that adequately assess left-wing extremism and its components (e.g., Jungkunz 2018; Schröder et al. 2020). We used the scale by Schroeder and Deutz-Schroeder (2015) to assess individuals with a more closed left-wing extremist worldview. We split our original sample along the arithmetic mean of this scale. Following the recommendations of the authors of the scale, individuals scoring high on the scale were identified as potential extremists due to their left-wing extremist world views (Schroeder & Deutz-Schroeder 2015). This is a debateable split-off, especially since cut-offs on attitudinal scales do not necessarily implicate serious extremism (Lösel et al. 2018). Our cut-off, however, is supported by the fact that individuals in the high risk group, indeed, reported significantly more politically motivated crimes than in the low-risk group.
Overall, our study can only offer cross-sectional insights into risk and protective factors for left-wing extremism and violence. Even though difficult to implement, only long-term studies can offer insights into different pathways as well as the relevance of different factors in different phases of extremist development (Junk et al. 2020; Lösel & Bender 2017).
While research on radicalization and extremism has increased, not much focus was put on left-wing extremism (Lösel et al. 2020; Treskow & Baier 2020). Our study contributed to the understanding and explanation of the phenomenon by looking at risk and protective factors in a high risk sample of potential left-wing extremists. On the individual level, risk factors such as criminal history and protective factors in the form of positive perceptions of procedural justice and legitimacy played a major role in committing politically motivated violence. Furthermore, our findings suggest that violent left-wing extremists are well embedded in an extremist environment. Additionally, our study offers insights into aspects that distinguish violent extremists who engage in violence towards property from those who also act against persons. Notably, more violence legitimating views were a strong indicator of committing violence against persons. Our study offers some insights into why high risk individuals turn to left-wing motivated violence and others do not, and what leads them to commit specific forms of violence. However, further research needs to move beyond cross-sectional designs and aim for longitudinal analyses of left-wing extremism and radicalization.
This research was funded by a scholarship from the Konrad-Adenauer-Foundation to the first author and partially supported by a grant from the European Commission to the co-authors.
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