I had a cousin who voluntarily checked himself into the hospital related to severe withdrawal symptoms (and had bouts of psychosis related to said with withdrawal - meth addictions are nasty). His mother stayed for awhile but had to leave for work. She was repeatedly guaranteed by multiple doctors and nurses that he could not check himself out and would be there for several days at least. They told her to come back the next morning.
Late that night, he was discharged. Not even "he checked himself out". The hospital discharged him (and that's over an hour ride away from home, btw - no hospitals in rural areas these days).
He had no phone and no wallet. According to staff, he tried to call his mother to pick him up, but couldn't remember her cell phone number (it had changed recently). He called his sister and left a message, but she was traveling and didn't get it until much later. According to the hospital, he tried to call several different numbers trying to get a ride home and they made him stop and made him leave. In a quite rough downtown area he was not familiar with. While clearly not in his right mind. At 2am. With no wallet, no phone, no nothing.
The hospital had his mother's contact info. They did not give it to him even when he requested it. They did not attempt to contact her in any way.
We still don't know what happened afterwards. His body was found four days later in the river and it had been there for awhile.
Forcibly discharging someone under those circumstances and refusing to even contact their emergency contacts is beyond belief. I'm furious about it. Apparently it's common and not even something there's any recourse for.