The offence was that he walked by her on the street and kept saying "Hey babe"
If you get on anyone's nerves enough, you'll be arrested. That's why there are so many vague statutes like disturbing the peace, trespassing, loitering, public drunkenness, "mob action" and a lot of others that basically amount to pissing off the wrong person. Until recently in my state, it was a felony to film a cop beating someone.
Even if you're not guilty of any of those laws, which is nearly impossible, you may still be arrested and detained for up to three days without even being charged or told of your offense. That's not a Constitutional violation and you can't sue the cops for it. In the worst jails in the US, there are also a lot of people in jail at any given time awaiting trial because they can't afford bail, who have been in there for longer than the maximum punishment for whatever they were charged with.
One of my professors was a prosecuting state's attorney for twenty years. He said what finally made him quit was that he eventually realized about 90% of the people he was sending to jail were no danger to anyone. They were just lovable loser type fvckups who weren't bright enough or sober enough to stay out of trouble in a system that was designed to send them to jail.