A hidden body camera may be legal unless it is being used in an area where there is an expectation of privacy, such as a locker room, and doesn't record conversations, according to A1-HiddenCamera.com and Rcfp.org. Body cameras that record conversations may have further restrictions in some states.
The District of Columbia and 37 states only require one-party consent to record conversations unless there is an expectation that the conversation is private, states CriminalDefenseLawyer.com. All other states, including California, Michigan and Montana, require all parties to consent before any conversation is recorded. If a conversation is recorded in these states, without consent, such recordings are not admissible as evidence in court and could result in civil or criminal penalties.