I think for a first offence people should receive something like a 2 or 3 day shackle. everyone deserves a warning before prosecuted for such a minor offence.
I have seen many people mainly new players under level 16 that don't fully know and understand the vague rules this game gives get shackled and have no clue why. There is no type of warning or anything. That's why every first offence should get a warning and maybe a 2-3 day shackle with a pop-up explaining exactly why they got shackled including the offence that caused the shackling. That way it will show the players what they did wrong and be temporary and allow them to redeem their mistake.