Here is my full quote, "Also note that jailing one is not a threat either, but something that happens in a legal way many times over every day and night."
The contention above is that he was threatened. He was not threatened. Getting detained is not a threat, but a sanction imposed by law officers.
You've got to be kidding me---this is some of the more tortured parsing I've ever seen on FR. The motivation behind the cop's statement was clearly to compel the kid to do something the kid was otherwise not inclined to do of his own volition, otherwise the statement would have never come out of the cop's mouth. To suggest that something bad might happen to you if you do not do something is the very essence of a threat.