I take it Washington doesn't have convict work crews? We had them out fighting forest fires last summer in Oregon. The county jail work crews do the trash pickup, pressure wash streets and parking structures, etc.
I volunteered on a search for a lost hiker years ago, the prison sent up some of the firefighter convicts you mentioned and I got talking with the guard who accompanied them. He said they actually do a lot of work there, learning auto mechanics et al and hopefully learning a trade and/or how to work when they get out.