At least in the US, a pump/ CGM is generally paid for by employer benefits which would generally cease if you were arrested as your employer would likely fire you? There'd be COBRA but it would be impossible to arrange supplies without a phone/ mail so you'd likely be left with whatever state-funded treatment would be made available to someone in that situation.
My dad was in the hospital a few years ago and his sugars were consistently between 350 and 400 while he was there. All they are trained to do is keep you out of hypoglycemia because it could end in fatality. When I was in the hospital a few weeks back the doctor told me most diabetics come in with 250 to 300 sugars and they see no reason to be concerned.
I've heard similar things, which really frightens me. With a T2, there is natural insulin production, so while running a BG that high can cause damage, the person is generally not going to slip into DKA. However, with T1s, a BG of 300 can quickly become a BG of 600+ and result in DKA. My endo, who is a bit more knowledgeable of T1 compared to most other adult endos I've seen, told me once that this is a not insignificant problem in the hospital setting. She has always emphasized to me that should I end up in the hospital, she needs to be contacted because of this very issue. Serious quality of care issue as far as I'm concerned, because it amounts to a medical establishment not understanding the basic condition which they might be treating!!!
I think the reason hospitals are hyper about hypos is because a hypo would obligate them to "HURRY!" which is one thing hospitals, except maybe the ER, are extremely poor at? If you "need" juice, the nurse who stumbles upon you twitching on the floor, has to take emergency measures, the doc has to evalute you, then he has to write an order for some dude in the cafeteria to get you some juice, then the juice arrives and, since that will probably take 45 minutes, they don't bother waiting and crank your BG up to 400 w/ IV dextrose and glucagon.
Marie, now there's a thought. I would love a wing for diabetics, although it would kind of depend on your reason for being admitted in the first place. When I had a knee replacement, my doctor gave orders for me to take care of myself on my pump, and I did. The nurses were interested in what I was doing, but I did it myself. But there was no substitute for being in the knee replacement wing, where we all learned to walk again.