The Electronic Frontier foundations (EFF) amd the American Civil Liberties Union (ACLU) have sued the federal government to obtain information about its tracking of mobile phone users, according to the IDG News Service on Wednesday.

The lawsuit was filed because recent court cases have revealed that some U.S. Attorneys have claimed to not need probable cause of a crime before authorizing the tracking of mobile phone users. A court order is normally required to do that.

"The information now in the public domain suggests that [the Department of Justice] may be engaging in unauthorized and potentially unconstitutional tracking of individuals through their mobile phones," according to the ACLU and EFF complaint. "Information pertaining to the DOJ’s procedures for obtaining real-time tracking information is vital to the public’s understanding of the privacy risks of carrying a mobile phone and of, more generally, the government’s expansive view of its surveillance powers."

"Signing up for cell phone services should not be synonymous with signing up to be spied on and tracked by the government," said Catherine Crump, a staff attorney with the ACLU.

A spokesperson for the DOJ said, "Law enforcement has absolutely no interest in tracking the locations of law abiding citizens. Instead, law enforcement goes through the courts to lawfully obtain data to help locate criminal suspects, sometimes in cases where lives are literally hanging in the balance, such as a child abduction case or a serial murderer on the loose."

Even so, the plaintiffs believe there is enough evidence to suggest that some corners have been cut in the past, and they’d like to examine the history to make sure the federal government is always following its own rules.

On the mobile phone side of the issue, Apple has taken measures in its SDK licensing to make sure that developers themselves don’t unwittingly write apps that could inadvertently violate the privacy or security of iPhone users with the location services that are growing in popularity.