A 1994 Memorandum of Understanding Between DoD and DOJ on (Military) Operations Other Than War and Law Enforcement, recently released via FOIA request, may provide the “smoking gun” evidence that the US government, military, and police departments have been covertly testing “advanced technologies” developed by ARPA (Advanced Research Programs Agency).
The following document spells out that advanced weapons technologies (including non-lethal weapons and C4ISR Command, Control, Communications, Computers Intelligence Surveillance and Reconnaissance technologies?) are secretly being tested, developed, and deployed by DOJ and Police Departments for OOTW (military Ops Other Than War):
Thus, the question posed in the following 2015 article by Ramola D (Is the US Department of Justice Secretly Permitting Local Law Enforcement & the Military to Assault American Citizens Using Covert Directed-Energy “Non-Lethal” Weapons?) is apparently answered in the affirmative.
The following NIJ (The Department of Justice’s National Institute of Justice) report a few years later in 1997 spells out further action: https://fas.org/irp/agency/doj/164268.htm