I suspect that most will be focussing on the “in prison” bit, no matter how you re-brand it.
But as above, not everyone in prison is a convicted criminal (obviously in addition to guards/staff and visitors).
‘Prisoner’ does rather imply guilt, rather than Dindu Nuffins just waiting for some bleeding heart liberal to cook up some spurious claim to ‘prove’ that their conviction was unsafe.
"Inmate" is good enough to describe those that are currently pickled in the Royal Hospital, can't be that offensive.There is nothing wrong with prisoner at all. It's what they are.
- a person who is kept in prison as a punishment, or while they are waiting for trial.
- a person who has been captured, for example by an enemy, and is being kept somewhere