What methods does the ADL use to classify incidents as 'right-wing terrorism'?
Executive summary
The Anti-Defamation League (ADL) classifies “right‑wing terrorism” by applying its Center on Extremism’s definitions of domestic terrorism and by cataloguing attacks, plots and foiled conspiracies that “best fit” those criteria — for example, its 25‑year dataset of 150 incidents drawn from violent and criminal acts by U.S. right‑wing extremists (ADL) [1]. ADL’s recent reports and datasets (including a 2025 right‑wing terrorism report and its Murder and Extremism series) count successful attacks, failed attacks and foiled plots and note ideological ties (white supremacist, anti‑government, anti‑abortion, etc.) as part of classification [2] [3].
1. How the ADL defines the category: “domestic terrorism” as the starting point
The ADL frames its work around a definition of domestic terrorism — “acts or attempted acts of terrorism in which the perpetrators are citizens or permanent residents” — and then selects incidents that “best fit” that definition for its right‑wing terrorism compilations [1]. ADL’s Right‑Wing Extremist Terrorism report explicitly includes successful attacks, failed attacks and foiled plots in its counts, signaling the organization treats planning and intent as well as carried‑out violence as qualifying criteria [2].
2. What gets counted: incidents, plots and foiled conspiracies
ADL’s datasets include a broad universe: killings, shootings, arsons and other violent acts, plus plotted or foiled attacks. The 2017–2022 synthesis and ADL’s standalone reports state they include “successful terrorist attacks, failed terrorist attacks and foiled terrorist plots,” and their 25‑year list draws from a larger set of violent and criminal acts tied to right‑wing extremists [2] [1]. The Murder and Extremism series tracks extremist‑related murders and links them to ideological currents such as white supremacy and anti‑government extremism [3].
3. Ideology and motive: how ADL attributes “right‑wing”
ADL assigns the “right‑wing” label by linking incidents to ideologies — white supremacism, anti‑government or anti‑abortion extremism are repeatedly named — rather than by party affiliation alone. The ADL report notes white supremacists accounted for a large share of recent attacks (e.g., 30 of 67 in a six‑year window) and ties killings to extremist ideologies in its Murder and Extremism findings [2] [3].
4. Sources and methods: public reporting, legal findings, and ADL judgment
ADL compiles incidents from press accounts, court records and law‑enforcement information and then applies its Center on Extremism’s review to determine which events “best fit” domestic terrorism and right‑wing extremism criteria [1]. ADL also offers interactive mapping and raw data downloads via its Center on Extremism for public scrutiny [4].
5. Critiques and limits: why some researchers dispute ADL’s approach
Independent reporting and critics argue ADL’s net is broad. Business Insider found that when restricting “extremist incidents” to legally classified hate crimes or clearly reported ideological motivation, only about 58% of ADL’s cited incidents over a decade met that narrower definition, implying ADL’s inclusion criteria capture non‑ideological violence with group ties [5]. Think‑tank and op‑ed critiques likewise allege ADL sometimes labels non‑ideological killings as “right‑wing,” with claims that about half of ADL’s tracked killings over a decade were non‑ideological and disproportionately classed as right‑wing in an AEI critique [6]. Those critiques hinge on differences between a broad public‑safety tracking approach and a stricter legal or media‑reported motive standard [5] [6].
6. Transparency and public tools: how ADL shares its work
ADL publishes reports (e.g., “A Dark and Constant Rage,” annual Murder and Extremism reports, and a June 2025 right‑wing terrorism report) and maintains interactive tools and datasets through its Center on Extremism for users to examine incidents by type, state and ideology [1] [2] [4] [3]. ADL removed a public “Glossary of Extremism” after political backlash in 2025, showing classification choices can spark controversy and political pressure [7] [8] [9].
7. Competing perspectives: public‑safety emphasis vs. definitional rigor
ADL’s stated mission is to monitor and expose extremist threats broadly to inform public safety; that leads it to include plotted and ideologically connected acts beyond only convictions or formal legal terrorism designations [1] [2]. Critics argue this amplifies counts relative to stricter standards that count only incidents legally charged as terrorism or clearly motivated by extremist ideology [5] [6]. Both perspectives are present in available reporting; ADL emphasizes comprehensive threat tracking, while critics emphasize tighter legal and evidentiary thresholds.
8. What reporting does not say (limits)
Available sources document ADL’s definitions, the types of incidents it counts, and public critiques, but they do not provide a step‑by‑step internal rubric listing every decision rule or weighting ADL uses when categorizing ambiguous cases; that level of internal coding guidance is not found in current reporting [1] [2] [5].
Bottom line: ADL classifies right‑wing terrorism using a definition of domestic terrorism, counts attacks, plots and foiled conspiracies tied to explicitly right‑wing ideologies, and makes its data public — a broad, public‑safety approach that draws both academic and media praise for comprehensiveness and criticism for including incidents that some analysts say would not meet stricter legal or media standards of “terrorism” [1] [2] [5] [3] [6].