Big Brother could face growing pains as technology fuels the government’s ability to keep tabs on people.

The Maine Civil Liberties Union has joined a national effort to find out just how often law enforcement uses people’s cellphones to track their whereabouts.

The MCLU has submitted Freedom of Access requests to 12 police agencies in the state and the Maine Emergency Management Agency, seeking a range of information about policies, procedures and examples of how they have used cellphone tracking technology. The request is part of a nationwide effort by the American Civil Liberties Union.

“No one would say it’s appropriate for law enforcement to follow an innocent person to church or to the liquor store or wherever, but cellphone technology allows law enforcement to do that. Our laws haven’t kept pace with new technology,” said Shenna Bellows, executive director of the MCLU. “As lawmakers consider these important privacy protections, it’s important to understand the scope of the problem we’re dealing with.”

Maine Public Safety Commissioner John Morris has suggested asking the MCLU to narrow its request, which police agencies say could be hugely time-consuming. He also has suggested that the agencies develop a unified response to the request.

Police say the standard way to obtain cellphone records is to get a court order, which requires showing probable cause to believe the person whose records are sought has committed a crime.

“Everything we do with regard to cellphone (records) requires court orders and warrants,” said Michael Sauschuck, Portland’s interim police chief.

He said the Freedom of Access request, as written, could be very time-intensive and challenging to fulfill.

The American Civil Liberties Union has had its affiliates submit similar information requests to 375 agencies in 31 states. The goal is to determine the extent to which police have been using cellphone tracking technology, whether they have obtained court orders to do so, and what policies they have to protect innocent people from such surveillance.

Americans are just realizing how much of their personal information can be collected by their cellphone companies. Companies can determine, within about 50 feet, where a person is at any time.

Cellphones — even those that aren’t so-called smartphones — are constantly sending out signals in search of the closest tower. Those signals can be used to determine where a phone is located.

That technology has proved helpful in police emergencies.

Cumberland County Sheriff’s Chief Deputy Naldo Gagnon said his agency has used cellphone location information only twice since he joined the department in November, and in both cases deputies used it to find people who were suicidal.

“If it was a criminal case, we do have to get a search warrant,” Gagnon said.

Falmouth Police Chief Ed Tolan, who represents southern Maine in the Maine Chiefs of Police Association, said agencies also have used cellphone information to locate missing people who might be in danger. Cellphone location data also is helpful when someone places a 911 call and doesn’t know where they are.

However, the same technology can be used in other ways.

Some cellphones can store a year’s worth of data, which could indicate where someone has been, though companies say the data is not typically accessible to a company or others, and is not used that way.

Some companies have created web portals that allow police to access cellphone location information once the access has been authorized by the company.

The existence of data on people’s movements and its potential use by law enforcement should be troubling for all Americans, Bellows said.

Using cellphone location to track a drug trafficker and a shipment of drugs is good police work, she said. Creating “digital fences,” where authorities are given information about any cellphone that enters a specific area, is not.

“To subject all of us, or large numbers of people, to cellphone tracking without reasonable suspicions or probable cause is problematic,” she said.

Bellows was aware of no instances in Maine in which cellphone location was used improperly, without a warrant, but said that is why the information request is important.

“Because this happens in secret, we simply don’t know the extent to which law enforcement have engaged in this practice,” she said. “We think it’s important law enforcement demonstrate for the public they are complying with the Constitution and following proper procedures for cellphone tracking.”

Robert Schwartz, executive director of the Maine Chiefs of Police Association, said the request may not turn up much.

“It’s certainly not something the police just do routinely,” he said, and there’s little chance that police would track somebody’s movements unless they had reason to be suspicious.

Congress will consider the issue and whether federal protections are necessary.

U.S. Sen. Ron Wyden, D-Oregon, and Rep. Jason Chaffetz, R-Utah, have proposed the Geolocation Privacy and Surveillance Act, which would create a legal framework for when and how government agencies, businesses and citizens can access and use cellphone location information.