most policies come into play because of prior incidents, some just become implemented. You never know how someone will react to being arrested, taken to jail etc, so everyone under arrest goes in handcuffs. If handcuffs spark a resistance in someone before they go on, that’s probably someone that would resist when they get to jail too…so I’d rather them be in handcuffs to avoid that issue arising. I also wouldn’t want to be driving someone to jail that is under arrest for whatever It may be, and sat in a car with them unrestrained. Lots of people are chill until they find out they’re about to go to jail, or until the reality sets in as we get there.
and by policy I mean anyone that’s arrested goes in handcuffs. If you’re old, injured, or visibly pregnant, the handcuffs can go in front, otherwise it’s behind the back.