I had a rather telling cop encounter way before bodycams were invented. I had just bought a new motorbike, and although the road tax was paid, the tax disc had not yet come through from the DVLA. A couple of cops spotted the empty tax disc holder and pulled me over. They were brusque to the point of rudeness. I should point out that it was winter and as well as a full-face helmet I was wearing a full-body waterproof nylon motorcycling suit. I pushed my visor up and answered them. The change in attitude was comical. Suddenly all polite and friendly, and "we've had reports of stolen bikes so we're conducting checks. Sorry to inconvenience you madam."
They obviously thought it was a man they were stopping. It was a perfectly reasonable stop, absolutely justified. But when they thought it was a man (or a youth) they were rude and belligerent. The minute they realised they'd stopped a young woman, all polite and even obsequious.