The study cited the
PIRUS dataset which defined the terms as follows:
Far-right - There exists a broad range of far-right beliefs and actors (often overlapping movements), including both reactionary and revolutionary justifications of violence. In its modern manifestation in the United States, the ideology of the far-right is generally exclusivist and favors social hierarchy, seeking an idealized future favoring a particular group, whether this group identity is racial, pseudo-national (e.g., the Texas Republic) or characterized by individualistic traits (e.g., survivalists). The extremist far-right commonly shows antipathy to the political left and the federal government. As a result of this heterodoxy, this category includes radical individuals linked to extremist religious groups (e.g., Identity Christians), non-religious racial supremacists (e.g., Creativity Movement, National Alliance), tax protesters, sovereign citizens, militias, and militant gun rights advocates.
Far-left - The far-left in the United States is essentially class-oriented and consists primarily of individuals and groups that adhere to belief systems based on egalitarianism and the mobilization of disenfranchised segments of the population. With roots in the leftist student movement and radical prison reform movement of the late 1960s, traditional far-left extremists generally sought the overthrow of the capitalist system, including the United States government, in order to replace it with a new, anti-imperialist economic order that empowers members of the “working class”. The traditional left included groups that maintained a distinct racial identity (e.g., Black Panther Party), which were motivated by a mix of economic grievances and race-based issues. Today, the far-left is more commonly identified by followers of animal-rights and environmental protection issues. While not all animal rights or environmental groups are inherently leftist in orientation (for instance, there are Green Fascists), the vast majority of these individuals and groups identify with leftist political positions and have thus been included in the far-left category for the purposes of this project.
In order to be eligible for inclusion, each individual must meet at least one of the following five criteria:
- Arrested/Charged: The individual was arrested for committing an ideologically-motivated crime. This includes arrests or their equivalents outside the United States.
- Indicted: The individual was indicted for an ideologically motivated crime. This includes indictments or their equivalents outside the United States.
- Killed in Action: The individual was killed as a result of his/her ideological activities. This includes being killed during the commission of an attack, including suicide, being killed during an attempted arrest/detaining by security forces, being targeted by security forces (even if not the primary target), and being killed in an unmanned aerial vehicle strike.
- Member of Designated Terrorist Organization (DTO): The individual is or was a member of a terrorist organization designated by the United States Department of State. Note: "Member" is defined broadly. This includes official members, individuals that the US government or another government claimed were members of a DTO (even if the group itself did not acknowledge the membership), and individuals which credible media sources link to the group (but not those based on pure speculation). It also includes individuals who claim membership in a DTO even if the group itself did not acknowledge membership.
- Violent Extremist Group Association (VEGA): The individual is or was associated with an extremist organization whose leader(s) or founder(s) has/have been indicted for an ideologically motivated violent offense. Note: "Association" is defined broadly. This includes official membership, membership claimed by a government, and self-identified association (even if the group does not acknowledge it). It also includes active participation in group activities, such as protests and newsletter subscriptions. "Association" does not include less active participation in group activities, such as signing a petition or listening to a speaker from the group at a public event.
In addition, each individual must:
- have radicalized in the United States,
- have espoused or currently espouse ideological motives, and
- show evidence that his or her behaviors are/were linked to the ideological motives he or she espoused/espouses.