These guys go around taping public servants to see the reaction that they get. Sometimes the officials will tolerate this, recognizing the freedom and transparency that American society needs. Or, they may call the cops lol. It grew out of the cop watch movement that started around 2016 and 2017 when those police shootings were really frequent, and is probably best thought of as an extension of that.
My favorite channel is Long Island Audit, and he'll try to educate the officials to show that he not only has a right to do this, but also has a valid reason. Here's a sample of his work:
The whole idea is that if they allow filming of tax funded and public entities, then that is a good sign that they are on the up and up. It also teaches police officers some amount of restraint in dealing with people filming them, otherwise the police may make a serious judgement error and hurt people unnecessarily.
