The Conclave doors to the Library and the Meeting room can be opened after locking from the inside.
It registers that the inside door locks, but the outside door remains unlocked and people can still enter.
Happened once in each room now to me when I used my key on the door.
Its like this on all transition doors that I've seen. Courthouse doors for example
they need an auto-lock script applied to them.
In the meantime, you need to learn how to lock doors behind you.
Stand by the door. Right click -> Unlock. Right Click -> Open Door. Before the door opens, Right Click -> Lock.
Door will open, Locked, and will be locked when it closes.