With Minnesota police agencies increasingly able to use recorded license plate and cellphone data to determine where you've been, and when, some state legislators want to rein in the high-tech snooping.

Top law enforcement officials, however, told legislators at a Tuesday hearing that the data is used solely to catch bad guys, not spy on everyday citizens, and that tying their hands on information-gathering could render their crime-fighting tools useless.

Their claim was met with skepticism by a panel of House lawmakers, who are looking at how to handle the growing use of surveillance tools.

"We as policymakers are in agreement that we're not trying to protect bad actors or throttle law enforcement's ability to keep the public safe," said Rep. Mary Liz Holberg, R-Lakeville. "However, we are concerned about the privacy of citizens, and law enforcement has gone far beyond using information for law enforcement purposes to fishing out of curiosity."

The hearing comes amid growing concerns — and new revelations — about widespread data collection efforts by the National Security Agency and other agencies. Earlier this week documents provided by former NSA contractor Edward Snowden revealed that the agency has developed the ability to grab personal data on smartphone users simply playing a game of "Angry Birds."

In Minnesota, multiple cases of privacy breaches by law enforcement officials who snooped into driver's license data have also caused alarm. Even legal methods have elicited worry, like license plate reading technology that can track vehicle locations, Global Positioning System tracking devices and cellphone exploitation devices with names like "Kingfish," that surreptitiously collect and store the information of cellphone users in a given area.

Rep. John Lesch, DFL-St. Paul, who chairs the House Civil Law Committee, said that once the Legislature is able to fully define law enforcement's surveillance capabilities, it can set boundaries on how to balance public safety and individual privacy. Lesch invited more than 20 law enforcement officers to testify at Tuesday's hearing. Only the heads of five departments showed.

Minnesota Department of Public Safety Commissioner Mona Dohman, whose department owns a Kingfish device that drew pointed questions, said her office would welcome a change in state privacy laws to address new technology. Dohman added that the department has made it a priority to prevent privacy breaches of personal information.

Holberg was incredulous at that claim, noting that former DNR employee John Hunt looked up the driver's license data of nearly 19,000 people between 2008 and 2012 before he was charged with a crime.

"May I remind you that your standard of review failed to flag the massive misuse of information in the DNR that made this whole thing explode?" Holberg asked. Dohman responded that since that breach, her department has established new system with stricter monitoring controls.

Minneapolis Police Chief Janeé Harteau said that her officers use license plate readers, which scan license plates and store the data on where and when a vehicle was seen. After the House passed a bill to prevent retention of data on noncriminals, Harteau urged lawmakers to allow police to keep the information for 90 days before deletion. Getting rid of non-suspect data immediately, she said, would "essentially negate this technology," which is used to combat crimes like assault and domestic violence. Lesch pressed Harteau on why the 99 percent of people who aren't suspected of a crime must have their data held for three months.

"I don't know what I don't know," Harteau responded. "And I don't know when I might need that specifically."

Jim Franklin, executive director of the Minnesota Sheriffs' Association, said crimes often are not discovered immediately, making data retention critical.

"The longer we hold the data, the greater the probability that you're going to find something to solve a criminal action," Franklin said. "Once that data is gone, it's gone, and that is one of the reasons we believe that holding the data is important."

As the two-hour hearing disbanded, Andrew Henderson of Little Canada packed up his video camera. Henderson, 29, awaits trial next month on charges of obstructing the legal process and disorderly conduct related to his filming of a police incident in the fall of 2012. He attended the hearing out of his own fears of how technology is being used — fears he said could be alleviated with stricter laws.

"Policies are key in this," Henderson said. "And they need to be followed."

Abby Simons • 651-925-5043