I don't have a perfect understanding of law, but I thought that police had to charge you with an actual crime to keep you in the cage - not violation of employer's policy - as much as some employers think their word is law, it's just not so. Now, having said that, I have to believe that there is a credible accusation of a crime in order to keep him there - otherwise he's a political prisoner and the city should be under state/federal investigation on civil rights charges.
If this proves to be as much of a farce as it appears, I hope he bankrupts the city.