Civil rights activists in Massachusetts have a habit of recording police activity without regard to whether or not something questionable is happening. Police in that state have routinely attempted to stop the recordings and have even either confiscated the cameras/phones or arrested those operating them. To avoid this, many civilians have taken to recording from hidden locations. The police have objected on the grounds that the First Amendment of the US Constitution does not protect secret activity.
A federal district court in Massachusetts recently held that the First Amendment’s freedom of speech does apply to recording the police, even from a a secret or protected location. Altho this decision does not apply nationally, its analysis looks sound. I expect the ACLU and others to continue litigating any case in which people are arrested for making such recordings, but it would certainly be nice if it were the recognized law of the land that it’s ok to record police activity. Period.
https://slate.com/technology/2018/12/right-to-record-police-massachusetts-aclu.html