One last comment about Ad-Seg: LE just can't "put" someone into Ad-Seg w/o the Jail Commander/Warden's approval. I've been retired almost 15 years and I believe it was Title 12 (Ca Laws) about inmate's rights etc . . .
If you want to know about jail/prison life, look up Title 12 and it will explain everything about jail/prison laws.
It's either Title 12 or 15, sorry for that.
It's 15, doh ! Been awhile for me, lol.
Don't know too much about Calif., but knew about Ariz. back in the day.
Protective Custody could be requested by an inmate, or initiated by the prison of said inmate who had a threat placed on him, directly or through information gathered through confiscated kites, yard scuttlebutt, or shotcaller conversations overheard and reported by a snitch.
Admin was high risk inmates, for the safety of other inmates and staff. The one's that could control the actions of a crew/group, hand down "punishments", approve rank, control contraband, etc., if they were in GP. And the unusually hostile with the short fuses.
Both scenarios DO NOT guarantee that they will work. There's always a way to get around the rules.
An inmate in Florence, 40 some odd years ago, was burned to death when another inmate got into the light housing of his cell and replace the bulb with a bulb fill with gas and dishwashing liquid. When lock down came for count, lights turned on, the bulb exploded.
Another inmate left the AB, requested being move to PC, officials didn't grant it, he lost his eye when another inmate walked by his cell and shot him with a zip gun. He sued and received a settlement.