Police nationwide have a new method for tracking suspects — one that they'd rather not let you know about.

It's simple: Attach a hidden GPS tracking device to someone's car when it's parked in a public place, and then see where it goes.

According to the Washington Post, cops have used this method to catch people suspected of murder, sexual assaults, burglary, drug dealing and even embezzlement.

"I've seen them in cases from New York City to small towns — whoever can afford to get the equipment and plant it on a car," a top criminal defense lawyer told the Post. "And of course, it's easy to do. You can sneak up on a car and plant it at any time."

Civil-liberties groups have cried foul, claiming it's an invasion of privacy and a violation of search-and-seizure laws. Judges mostly disagree, ruling that cops don't need warrants to find out what happens on public property, which includes most roads and streets.

Still, police aren't happy that this formerly secret method is being revealed.

"We don't really want to give any info on how we use it as an investigative tool to help the bad guys," a Fairfax County, Va., police spokeswoman told the Post. "It is an investigative tool for us, and it is a very new investigative tool."

• Click here to read the rest of the story in the Washington Post.

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