Okla. Stat. tit. 15, § 503

It shall be the duty of the proprietor, manager, or operator of any hotel, apartment hotel, or inn to equip the doors of all guest rooms in any hotel, apartment hotel or inn operated by him, with suitable night latches, night chains, or bolts, so placed on the inside of such doors, as to prevent such doors from being opened from the outside by key or otherwise. Laws 1939, p. 341, § 1.