Beware the Lock Bump, the Burglar’s Latest Technique

Lock bumping has been around for a few years. Apart from a few news magazine stories, it hasn’t received a lot of play in the media. At first, homeowners expressed concern, but that faded as the coverage faded, mostly due to the lack of criminal statistics on lock bumping.

Upon responding to a burglary call, police find the likely point of entry and examine for damage to the home. A lock bump leaves virtually no trace, unless the process is performed poorly. Hence, statistics for lock bumping are inaccurate since those incidents are normally categorized as “no visible sign of entry” by the officer on the scene.

Let’s look at what lock bumping is and how it’s performed. To start, a brief overview of how locks work is necessary.

As a key slides into a lock, the pins inside the lock slide across the notches and valleys cut into the key, lifting and lowering the pins. When they’re properly aligned, the cylinder can be turned and the door can be opened. A bump key takes advantage of this.

A bump key is made by filing v-shaped notches into a key at the points where the pins coincide inside the lock. When the bump key is inserted into the lock, it is aligned with the pins, although it cannot move the cylinder. By applying a bit of lateral torque and simultaneously bumping or tapping the key with a rubber handled tool, the pins in the lock pop up momentarily. This is long enough for the key to turn the cylinder and open the door.

While there are numerous brands of household deadbolts, they’re all based on the original Yale design, meaning they’re all vulnerable to lock bumping. With a thorough set of bump keys, the vast majority of homes can be opened in two seconds with very little noise.

Currently, the only solution is to buy a high security lock Mul-T-Lock or Abloy locks that use rotating disks or pins on the bottom of the lock to defeat lock bumping. They’re priced reasonably and will reinstate your peace of mind.