The ACLU is contacting law enforcement agencies to ensure that they aren’t illegally tracking your movements.

On Wednesday, the ACLU of Washington sent out public records requests to Bellevue, Tacoma, Yakima and Spokane. The group hopes to obtain information about how police use citizen’s cell phone records.

Each agency is being asked to share information on their policies and procedures used for acquiring cell phone location data. That includes how frequently police try to access someone’s whereabouts via cell phone records and the issue of warrants.

“We want to start getting a handle on whether law enforcement is getting this information without using a warrant and without evidence that someone is involved with criminal activity,” said Doug Honig with the ACLU of Washington.

This spring, researchers revealed that iPhones were collecting and storing location information in unknown files on the phone.

Other recent phone-tracking controversies have also brought attention to the tracking issue.

According to the ACLU, the National Security Agency suggested to members of Congress that the NSA might have the authority to collect location information of American citizens inside the country.

The ACLU also said that in Michigan, police sought information about every cellphone near the site of a planned labor protest.

The local requests are a part of a coordinated information-seeking campaign. In all, 379 requests have been sent to police departments, big and small, around the U.S.

“A detailed history of someone’s movements is extremely personal, and government should seek such information only with a warrant based on clear suspicion of criminal activity,” Brian Alseth, director of the ACLU-WA Technology and Liberty Program, said in a news release.

Honig adds, “We think it’s important that warrants be used and it be based on the belief that someone is doing something against the law.”

Currently, congress is considering the Geolocation Privacy and Surveillance Act, a bill supported by the ACLU. It would require police to get a warrant to obtain personal location information and would protect both historical and real-time location data.