Keep Factually independent
Whether you agree or disagree with our analysis, these conversations matter for democracy. We don't take money from political groups - even a $5 donation helps us keep it that way.
How have FBI domestic terrorism arrests for far-right and far-left groups changed over the last decade?
Executive summary
FBI public reporting and independent datasets show a rise in domestic terrorism attention and arrests tied largely to the far right over the past decade, with the bureau reporting 355 DT-related arrests from 2016–2018 and an increase in investigations from about 850 to 2,700 people in recent years (FBI summary and PBS reporting) [1] [2]. More recent independent analyses through 2024–2025 identify a complex picture: right‑wing violence historically caused most deaths and many arrests, but some 2025 studies and reporting find increased left‑wing incidents in the first half of 2025, prompting debate about whether enforcement and threat environment have shifted [3] [4] [5].
1. What the FBI has publicly counted and how that changed
Congressional and FBI documents show the bureau began publishing more systematic domestic‑terrorism (DT) data after 2019; for example, the FBI and DHS produced a strategic assessment in 2021 and the Congressional Research Service notes tables the FBI provided on arrests and investigations for 2015–2021 [6] [7]. Wikipedia summarizes an FBI figure that 355 suspects were arrested on DT‑related charges from 2016–2018, illustrating early‑period baselines used by researchers [1]. Separately, PBS quoted FBI investigators saying active DT subjects under investigation rose from roughly 850 to about 2,700 in a multi‑year span, indicating expanded caseload and attention [2].
2. Far‑right arrests and lethality dominated the last decade
Multiple official and independent sources emphasize that far‑right extremists produced the majority of lethal domestic terrorism attacks and have driven many arrests in the 2010s and early 2020s: the FBI and DHS, and later journalists and analysts, pointed to white‑supremacist and anti‑government ideologies as the chief driver of DT threats and many arrests [6] [3]. Reporting and studies document high‑profile arrests and prosecutions tied to Proud Boys, Oath Keepers, militia actors and “boogaloo” adherents in response to plots and violence around and after January 6, with those prosecutions contributing significantly to federal DT arrest totals [8] [2].
3. Data limits — why arrests aren’t a simple trendline
Congressional analysts stress the FBI’s DT data have limits: published counts cover arrests, referrals and investigations but do not fully capture classification changes, parallel state prosecutions, or how coding choices shape totals [7]. The NPR and PBS pieces note the bureau and researchers have adjusted definitions and added new categories (e.g., “nihilistic violent extremism”), complicating direct decade‑long comparisons of arrest counts [4] [2]. In short, rises in “investigations” can reflect policy emphasis, new reporting and reclassification as much as change in raw offender numbers [7].
4. The contested 2024–2025 shift: left‑wing activity and fresh analyses
Analyses published in 2025 sparked debate: CSIS and other researchers found that in the first half of 2025 left‑wing incidents outpaced far‑right ones for the first time in decades, and outlets like Axios and NPR explored whether that reflected real change or artifacts of sampling, coding and short time windows [5] [4]. PBS and earlier government material, however, still document that over the longer term the right produced the lion’s share of deaths and many arrests, underscoring a divergence between shorter‑term snapshots and decade‑long patterns [3] [6].
5. Enforcement choices and political context affect arrest totals
Commentary and reporting note that who gets investigated and arrested depends on Department of Justice and FBI priorities, leadership changes, and political pressure. The Guardian reported concerns that leadership shifts could deprioritize far‑right investigations; other studies document vigorous federal prosecutions of groups tied to January 6 [9] [8]. These shifting priorities mean arrest counts can rise or fall for reasons distinct from underlying violence rates [9] [7].
6. Bottom line and what the coverage does and does not say
Available reporting shows far‑right actors accounted for most DT‑related arrests and the majority of lethal domestic terrorism across the 2010s and early 2020s, with documented FBI arrest totals such as 355 for 2016–2018 and an expansion of active investigations from about 850 to 2,700 in recent years [1] [2] [3]. At the same time, 2025 research highlights a near‑term uptick in left‑wing incidents, and analysts caution that definitional changes and enforcement priorities make decade‑long arrest comparisons imperfect [5] [4] [7]. Available sources do not mention a single definitive, consistently applied decade‑long arrest series by ideology that would allow a neat graph of “far‑right vs far‑left arrests” without caveats [7].
If you want, I can compile the specific FBI tables from the 2015–2021 submissions cited by Congress and extract the arrest counts they list, which would let us produce a conservative, source‑linked timeline [7] [6].