WASHINGTON, DC - The U.S. Supreme Court said Monday it will decide if police officers need a warrant to collect location data from cell phone companies.

Currently, the law varies from state to state regarding whether police need a warrant or can simply ask the phone companies for that data.

Investigators can use the phone's location to pinpoint where the phone's owner was, and determine if, for example, the phone was near the scene of a crime.

The case hinges on a 40-year-old Supreme Court decision that phone company data is not private because the phone's user willingly allowed a third party to collect it.

However, that decision was made decades before GPS technology and the advent of technologies that can track every move a person makes.