To add to this, it doesn’t really matter what you’ve done (or not), it matters what they’ve been told you did and how convincing the complainant is to them. So the “how bad do you have to fuck up” part of your question is answered by: you don’t have to fuck up at all.
I once had cops show up at home looking for me after someone who didn’t like me simply saw me driving behind them for a few minutes earlier that afternoon. Apparantly they told the cops some horror story about me stalking them and were in fear of their life or some such nonsense. After talking a few minutes they left and I never heard from them again.
I’ve heard that sometimes the cops will decide that it’s serious enough to get an arrest warrant, but not serious enough to actually show up on your doorstep. So the warrant gets filed and three years later you are pulled over for a traffic violation and the cop sees the warrant and you are finally arrested and assigned a court date for that old offense. Does that actually happen?
My brother-in-law had cops come to his door and arrest him for 2 speeding ticket that he hadn’t paid – issued by one of those little podunk towns that survive on speed trap ticket revenue. Somebody in the town issued a warrant and he was arrested half a state away.
The only thing that kept me out of prison when I was young was being white in America. Evidently my worst crime ever was not paying a ticket for an expired inspection sticker I got in Waco, Tx. 3 months went by and I got a phone call: “Slow, this is Trooper Jackie Wallace. I have a warrant for your arrest on that inspection sticker and I need you to come on in.” For the next few years Trooper Wallace dogged my every move, every address change, every new phone number, he always found me, never quite got the cuffs on me. One day a roommate of mine answered the phone and, knowing the history, told Trooper Wallace I’d run out of friends in Texas and moved out to California, nobody knew where, but if you find the son of a bitch he owes me money! The search moved west and I was free…
Cops showed up at my apartment about 7 years ago when I was doing the armored gig. I wasn’t there at the time and the officer left his card and asked me to call. I did and found that I’d been accused of driving off at a gas station 1 mile from my apartment. I ran over there to find the assistant manager accusing me of driving off without paying for $25 in gas. I said I paid cash at this particular register. I was absolutely furious, as any doubt would cost me my job. Cop made them pull and count the register. It was over by not quite that amount. Assistant manager says it isn’t enough to clear me, cop turns to me and says “There’s no crime here, you can go”.
I wrote to the company, asked if they had video. Turned out they did. I paid. Company sent me a bunch of car wash coupons and a gift card by way of apology. I never used them. I wasn’t looking for ‘compensation’, I was only looking for an apology. Also refused to go near the place for the better part of a year - when I drove by it twice a day.