It's after an arrest -- whether or not there was a crime is determined at trial. The idea is both to make sure that people show up for court and to have a boun

It's after an arrest -- whether or not there was a crime is determined at trial. The idea is both to make sure that people show up for court and to have a bounty to give to bounty hunters if they do not to enforce compliance, rather than putting that on the police themselves, because there just aren't enough cops around to round up everyone who simply wouldn't show up otherwise. But yeah, being poor is effectively a punishment in and of itself and not just in this circumstance, either.