Who Is At The Door?

My sister made arrangements for the two of us to spend the weekend in a historic 'haunted' hotel called the Menger. It sounded like fun. At 3 a.m. on Friday, security tapped on the door. It was open! Not thrown wide open, but about three inches open. I dead bolted the door before turning the light out and there is no obvious way to open the deadbolt from the outside. My sister is a fan of paranormal tv shows and she thought this was great. It spooked me but not in a good way. Who opened our door?!? Most hotel clerks would be concerned. When we told the desk clerk she said that the spirits had been active. Lol, I talked my nephew (a policeman) into spending Saturday night on an air mattress not far from the door. I wanted police protection.