A lock bar for controlling the position of a railroad warning gate includes an elongated body portion extending between a first end and a second end, a clutch mechanism disposed in the elongated body, the clutch mechanism permitting rotational movement in one direction but restricting rotational movement in the opposite direction and a hub disposed in the clutch mechanism for engaging a portion of a motor drive mechanism for a railroad warning gate such that the gate is permitted to move in one direction but is restricted from movement in the opposite direction. Indicia are preferably disposed on the opposing edges to indicate the position that the warning gate will be retained in. An oblong aperture defined through the lock bar receives a pin to hold the lock bar in engagement with the motor drive mechanism.