We don’t use shackles, and the only ones who do this are sentenced by the courts to weekends in jail and the menial labor. DWI and other assorted convictions, but not “hard” criminals. I encounter them at the fire station where they often work cleaning. If they walk away, they end up back before a judge with fewer options. Maybe straight jail time, so the weekend thing is preferable.
Sorry, I was talking about two different details - yes the ones doing our road clean up are probably like yours, minor issues or community service. The guys working the fields were actually from a prison, not the sheriff’s office or whatever was being used for the roadside clean up