Yes you can legally force somebody to go to the hospital, at least in the Commonwealth of Virginia. Its called a Medical ECO or a Medical TDO, both of which require orders from a magistrate and have time limits. Its a complicated process but at least in VA there is a magistrate on call 24/7
An ECO is only for transport and last for only 4 hours.
A TDO is for when the patient needs to stay at the hospital.
There are restrictions of course but I need to talk to my teacher about those again because my slides are vague. Hope this is interesting and helps the discussion.