The FBI defines domestic terrorism as "the unlawful use, or threatened use, of violence by a group or individual based and operating entirely within the United States (or its territories) without foreign direction, committed against persons or property to intimidate or coerce a government, the civilian population, or any segment thereof, in furtherance of political or social objectives."
TheGuardian.com counts 585 Americans killed by police to date in 2016, which is on track to match the previous year's record of 1,134. Police disproportionately intimidate, coerce, and kill people of color, those with disabilities, and the poor, to exercise social control, to extort fines and fees, and to seize property.
The police are the single deadliest terrorist group in the United States.