Extremism in the United States: Looking Back on 2020

Each year, the Anti-Defamation League (ADL) collects and tracks data on murders that occur as a result of extremism. In their latest report, Murder and Extremism in the United States in 2020, the ADL states that there was a significant decrease in deaths by domestic extremists, with 2020 having the lowest number of yearly deaths since 2004.  While that may come as welcoming news, the ADL warns that extremists were still as active as ever, noting that there were “16 right-wing extremist-related terrorist plots/attacks in 2020 (through November), an increase from the 13 documented in 2019.”

The ADL speculates that the decrease in deaths may be due in part to an “absence of mass shooting sprees or other mass casualty attacks,” pointing out that there were 17 deaths amongst 15 separate incidents.  The ADL also clarifies another important consideration:

A number of deaths occurred during or near protests in 2020. It’s not possible to arrive at a universally agreed-upon total for those fatalities, because there is no set criteria for inclusion. A couple of these deaths were identifiably extremist-related and are included in this report. Most, however, are not (although some are still under investigation by law enforcement).

The report provides some details on each case noted in the above statistics, along with other cases that were speculated to be in connection to extremist groups, but were either determined not to be domestic terrorism, were inconclusive, or are still under investigation.


Additional resources on extremists and threats can be found on the HSDL Timeline and in our Featured Topics on Domestic Terrorism, and Lone Wolf Terrorism. Please note: HSDL login is required to view some of these resources.

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