Provided is a crossbow safety system comprising a crossbow, optic fence, and interlock. The crossbow may have a bowstring operable between a cocked and an uncocked position, the cocked position and the uncocked position defining between them a bowstring plane, and a trigger assembly adapted to selectably retain the bowstring in the cocked position. The optic fence may be adapted to detect an obstruction in a safety plane coincident with the bowstring plane or offset below the bowstring plane by some offset distance. The optic fence may have an infrared emitter adapted to output IR radiation, and a photodiode adapted to sense the output IR radiation from the infrared emitter. The interlock may be operationally engaged with the optic fence and the trigger assembly. The interlock may be adapted to lock the trigger assembly from releasing the bowstring if the optic fence detects an obstruction in the safety plane.