Ninja Rock Crime

Learn about the legality of possessing ninja rocks, which are often used as burglary tools.

A “ninja rock” is a broken piece of a spark plug, specifically a small piece of the ceramic portion of the plug. Those ceramic pieces—typically made from aluminum oxide ceramic—are harder than tempered glass. Even though they are very small and light, they can break tempered glass much more easily than, say, a steel tool such as a hammer or crowbar. Because of their small size, ease of concealment, and ease of use, many thieves use these ceramic pieces to quickly break car windows, display cases, home windows, or anything else made of glass.

Not surprisingly, at least one state has made it a crime to possess ninja rocks, while other states have laws that can apply in situations where a person is found with ninja rocks in his or her possession.

Ninja Rocks in California

California is the first state to specifically address ninja rocks in its criminal laws. California Penal Code Sections 466-469 make it a misdemeanor offense for anyone to possess a range of burglary tools, including ceramic or porcelain spark plug chips or pieces, with the intent to break and enter into any vehicle, building, vessel, aircraft, railroad car, or trailer coach.

Possession of Burglary Tools

While California appears to be the only state that specifically identifies ceramic spark plug chips or pieces as illegal, other states have laws that can apply in the same circumstances. Many states have laws that make it illegal to carry any tool that is specifically made or adapted for the purposes of committing an unlawful entry into a building, vehicle, or other area. For more information, see our article on Burglary Tools.

As an example, in the state of Missouri it is a felony offense to carry any such burglary tools with the intent to use them to commit an unlawful entry. (Missouri Revised Statutes Section 569.180) The general language of Missouri’s law, and laws in states with provisions, means that you could be charged with a crime if you’re found with ninja rocks even if the law doesn’t specifically describe them.


The California ninja rock law, as well as similar burglary tool laws in other states, makes it a crime to possess ceramic spark plug pieces if you intend to use them to commit a burglary or illegally break and enter somewhere you don’t have permission to be in. In such cases, a prosecutor does not necessarily have to present direct evidence of the accused person’s state of mind in order to prove intent. It’s usually enough for the prosecutor to show that the circumstances surrounding the situation are enough to lead a reasonable person to believe that the accused intended to commit a burglary.

In at least one state, Washington, an appeals court has ruled that even though two men illegally entered a house through an unlocked door, their possession of ninja rocks at the time was enough to show that they intended to break in and commit a burglary.

Ninja Rock Penalties

Because criminal laws differ among states, anyone convicted of a ninja rock related crime faces a range of possible penalties. For example, if you’re convicted of misdemeanor offense you could face up to a year in jail, as well as fines of up to several thousand dollars. A felony offense, on the other hand, could lead to lengthy prison sentences and even higher fines.

It’s also possible for a court to sentence you to probation for a ninja rock crime. Probation usually lasts at least a year, during which time you must pay all related fines, and report to a probation officer, and comply with all the court’s orders or you risk having to serve the original jail or prison sentence.

Further, in any case where your actions resulted in property damage, a court can order you to pay for the damages, known as restitution, in addition to any fines or court fees.

Find a Lawyer

If you’re found possessing ninja rocks, regardless of the state in which you live, you could face criminal charges. If convicted, depending on the circumstances of the crime and the state in which you live, you might face serious jail or prison time. Whenever you’re facing a criminal case, even if you haven’t been charged yet, you always need the advice of an experienced criminal defense lawyer in your area. A lawyer who knows state law, has handled cases in the local courthouses, and who can negotiate with prosecutors on your behalf is the only person who can give you advice about your case and what you need to do. Contact a local criminal defense attorney as soon as you’re approached by the police or are charged with a crime.


Talk to a Defense attorney

We've helped 95 clients find attorneys today.

How It Works

  1. Briefly tell us about your case
  2. Provide your contact information
  3. Choose attorneys to contact you