If you own a bump stock, you could soon become a criminal.

The Justice Department has effectively banned them by reclassifying them as machine guns. Which means anyone who owns one must either destroy or surrender the device before Tuesday.

And if you don't, congratulations: You're now breaking federal firearms law.

After the Las Vegas shooting, where a madman used a bump stock during his shooting spree that killed dozens and injured hundreds, there was a nationwide push to get rid of the things.

President Donald Trump declared that he would ban them without congressional action and directed the Justice Department to figure out how.

The department's quick and dirty solution was to reclassify bump stocks as machine guns using an existing law: The National Firearms Act of 1934. This means no new bump stocks can be manufactured.