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Domestic Extremists and Social Media: Study Finds Similarities, Differences in Web Habits of Those Engaged in Hate Crimes Vs. Violent Extremism

NIJ-sponsored study, bridging two leading databases on extremist hate and violence, found that individuals in both have been influenced by social media, and their web platform choices may mirror those of the general population.
Date Published
April 19, 2022

Isolating and comparing the social media habits of two distinct types of extremists can better prepare justice system agencies to prevent and respond to extremist violence in the United States.

Research sponsored by the National Institute of Justice has found that study samples of individuals in the United States who have engaged in violent and non-violent hate crime and other forms of extremist crime were influenced by social media.

A key finding was that extremists in the study group may mirror the general population in their use of various social media platforms, particularly in terms of reliance on Facebook. Although the sample size was relatively small, and less than 20% of the study sample said they used Facebook, use of Facebook was found to be significantly higher than that of any other social media platform.

The National Consortium for the Study of Terrorism and Responses to Terrorism, or START, conducted the study of social media usage as a part of a broader investigation tapping two major national databases of extremist events and individuals:

  • ECDB - Extremist Crime Database. ECDB is a database that keeps track of violent attacks, homicides, and financial crimes carried out by extremists inside the United States. Attacks tracked in ECDB include bombings, shootings, or other violent assaults that resulted in at least one death. The database primarily, but not exclusively, tracks left-wing, jihadist, and right-wing extremists.
  • PIRUS - Profiles of Individual Radicalization in the United States. PIRUS is a database of individuals in the United States who radicalized to the point of violent or nonviolent ideologically motivated criminal activity, or ideologically motivated association with a foreign or domestic extremist organization. The PIRUS database includes individuals who would commonly be considered perpetrators of hate crime, that is, spontaneous violent or threatening acts against another individual on the basis of gender identity, race, ethnicity, religious affiliation, or sexual preference. In the PIRUS database, individuals are anonymous.

The research examined 2,100 cases in ECDB and 1,500 cases. Of these cases, 454 individuals in the PIRUS database were matched with individuals identified in ECDB. 

Social Media Use Study Segment

In a study segment focused on use of social media by extremists, the researchers searched in multiple social media platforms for data reflecting use of a specific platform by individuals found in PIRUS or ECDB and associated with a successful or failed act of violence or fraud undertaken to advance an ideological agenda. The team selected 52 individuals meeting that criterion. Of the 52, PIRUS was the source of 34 individuals, 12 came from ECDB, and six appeared in both datasets. The study team examined available case histories, including demographic and incident details, as well as publicly available open source data. The case-history review supported creation of search terms to identify the individual or individuals associated with a given incident and the social media platforms they had used.

The 52 selected subjects included:

By Ideology:

  • 21 individuals motivated by radical Islamist ideologies
  • 29 individuals motivated by radical right-wing ideologies
  • Two subjects associated with far-left groups

By Database Source:

  • 34 from PIRUS
  • 12 from ECDB
  • Six from both datasets

The study concentrated on cases occurring after 2007. This period has seen a significant rise in the use of Facebook, Twitter, and other social media platforms, the researchers’ report noted.

Findings on Social Media Use

The researchers found the following social media platform use within the study population:

  • Facebook was the most common platform, with nine users (17.2%).
  • More individuals motivated by radical right-wing ideologies had Facebook accounts (13.4% of the sample) than individuals motivated by radical Islamist ideologies (3.8%).
  • Twitter and YouTube accounts were identified for 5.7% of all subjects.  
  • Twitter use was slightly higher among Islamists (3.8% of the sample), proportionately, than far-right extremists (1.8%).
  • Instagram use was uncommon; only two far-right and one Islamist account were identified.
  • Directly identifiable personal websites were found for 5.7% of the total sample.
  • Involvement in online forums was confirmed for 3.8% of subjects, with one additional subject deemed questionable for forum involvement.

Implications and Conclusions on Social Media Use

Results of the social media research segment suggest that patterns of use of different platforms vary across ideological groups and may reflect general use of these platforms within the larger population. Differences may also reflect diverging interests of individuals in the groups. The research report noted a need for more research examining the use and quantity of social media messages expressing ideological beliefs within and across radical ideological agendas.

Other Study Segments

The social media use study was part of a larger research project encompassing two other major elements:

  • An analysis of the radicalization history of the 454 individuals linked across the two datasets, (PIRUS and ECDB).
  • An analysis of 38 case studies examining indoctrination or radicalization processes of criminal extremists, selected from ECDB and PIRUS. Criminal extremists have committed nonviolent crimes, targeted violence (hate crime), or politically-motivated violence (terrorism).

Both datasets contained individuals associated with nonviolent extremist acts, as well as others associated with violent extremism. A notable finding of the study element on radicalization history was that individuals in the linked PIRUS/ECDB dataset were more likely to be violent, with 61% in the linked set likely to engage in violence, than non-linked subjects, of whom 38% were likely to engage in violence. That was especially true for those with a radical Islamist ideology (90% of violent PIRUS cases linked).

The study element on indoctrination or radicalization processes examined whether “social control” and “social learning” processes varied across extremists engaged in hate crimes, versus those engaged anti-government or anti-society violence. Social control is a theory positing that whether or not individuals engage in crime is determined by the strength of their bonds to society. Social control theorists assert that all individuals are motivated to offend, but some are constrained by formal and informal regulatory forces. Social learning is a theory based on the idea that crime is a behavior learned from others. Social learning theorists maintain that criminality is a learned behavior like other conduct, informed by social relationships.

Using a case study method to focus on four extremists drawn from PIRUS and ECDB — two holding far-right radical beliefs, and two holding radical Islamist beliefs — the researchers found significant similarities and differences across ideology and types of individuals committing the crimes. The findings offered preliminary evidence supporting aspects of social control theory, especially the role of peers in facilitating social relationships that increase radicalization and crime, but less support for a role of social learning in the radicalization process, according to a separate report by the researchers.[1] Because that element of the research was preliminary, the researchers said, further study was needed to examine the extent to which both theories can account for the radicalization process generally.

About this Article

The research described in this article was funded by NIJ award 2015-ZA-BX-0004, awarded to the National Consortium for the Study of Terrorism and Responses to Terrorism, University of Maryland, College Park. This article is based on the grantee report “Social Learning and Social Control in the Off and Online Pathways to Hate and Extremist Violence,” by Gary LaFree.

Date Published: April 19, 2022