I want to write a paper on what crime in daily life was for the average roman, how personal property was defended, descriptions of criminals or roaming brigands, quantitative measures of crime if possible. Any of you know any primary sources, or sources in general, for these kind of things?

I'm actually interested in this because there doesn't seem to be that much of a law enforcement force, so the state didn't try to get a "monopoly" on violence:

http://www.reddit.com/r/AskHistorians/comments/zkdts/what_was_law_enforcement_like_in_ancient_rome/

I'd like to see how that effects Roman society.