Baker act from a med surg nurse

Hi,
out of my area and much confusion as to the rules. Elective surgical pt, last week an od, 2 in the last 3 weeks. PCP rights "pt at high suicide risk, needs a sitter". Hospital doesn't do sitters without one. MD won't sign. Psych comes in next day, (sitter was supplied), states pt is a risk, but still won't sign one. Later on in the day, UM are insisting. Psych agreed but wouldn't come back to sign the paperwor, faxed back a completed form. Now, is this legal or not? Conflicting info; in the end he got a sitter, was in no way trying to leave etc. But still would like to know the answer. Thanks in advance