In Dallas County Mental Health & Mental Retardation v. Bossley, 968 S.W.2d 339 (Tex. 1998), a mentally ill patient escaped through unlocked hospital doors and later committed suicide by leaping in front of a truck. 968 S.W.2d at 340-41. We concluded that neither the use of tangible property -- unlocking the hospital doors -- nor their condition -- being unlocked -- caused the patient's death. Id. at 343. The doors may have "furnished the condition that made the injury possible" by permitting the patient to escape into the community where he committed suicide, but "the use and condition of the doors were too attenuated from the patient's death to be said to have caused it." Id.