Purely anecdotal, grain of salt, and all that, but I have LEOs/firefighters/paramedics in my family. Consequently, I also have several family friends who are in those fields. Almost all of them have given me some variation of the "don't trust a cop, ever" speech. Which boils down to basically:
He's not your buddy looking to help you out of a pickle. He can and will fuck you in various ways. The average American, as a routine course of daily life, violates at least 5 laws a day, often without any thought or notice. Cooperate, but keep your mouth shut outside of responses to lawful commands.
Which is precisely why, at least in certain jurisdictions, I, as an average, decently educated and successful white dude, am MORE likely to catch a bullshit charge. A lot more shit goes by the wayside from "Its cuz I'm black, huh?!?" than you think. They make up the numbers by coming down harder on the average joe. At least, in certain jurisdictions. Or so I am told. Again. grain of salt.