A 14th Amendment S1983 action alleging excessive force in the use of acoustic weapons states a claim where the force is intentionally applied and the officer is aware of its unreasonable use, given lack of exigency, proportionality of response, and mitigation.
http://www.ca2.uscourts.gov/decisions/isysquery/594b7f87-3c10-48a4-8c8c-42b1d446d0a8/1/doc/17-2065_opn.pdf#xml=http://www.ca2.uscourts.gov/decisions/isysquery/594b7f87-3c10-48a4-8c8c-42b1d446d0a8/1/hilite/
Since 2011. An occasional commonplacing of the U.S. Circuit Courts of Appeal.
Neither an authoritative statement of the law nor legal advice. Quick work.