Abstract: A rectangular shaped lock-block with its forked interface hinge which is joined by a common axle which also serves to hold the interface hinge firmly against the toilet seat and lid and hold the lock-block device firmly against the rear of the toilet basin behind the toilet seat. The lock-block device houses a spring-latch mechanism with a removable compression spring which is held in place by a set screw located at the rear of the lock-block device. The compression spring exerts a constant pressure against the latch which is forced under the interface hinge holding it and the toilet seat lid in the down locked position. The latch must be retracted before the lid and seat can be raised. Once the hinge and lid are raised out of the locked down position, the spring forces the latch to ride against the rotating hinge and automatically relocks when the lid is lowered to the down position.