A bipartisan group of Minnesota legislators says the state's use of location-tracking data from ignition interlock devices in the cars of drunken-driving offenders is unconstitutional — and they intend to try to stop it early in next year's legislative session.

Rep. Peggy Scott, R-Andover, and Rep. John Lesch, DFL-St. Paul, said Monday that they will introduce a measure that would restrict the Department of Public Safety's ability to track the movements of the approximately 11,000 people who use an interlock device as part of their sentence.

The department has been using the devices, which analyze a driver's breath to check for sobriety — and won't allow the car to start if the driver has had too much to drink — since 2010.

More recently, however, it has been ensuring that each device is able to immediately notify officials of where and when violations occur.

Scott, the chairwoman of the House's civil law and data practices committee, said the Legislature did not intend to grant state officials that power when it approved the use of the devices. She's now concerned it could leave the state open to legal challenges.

"The purpose of the ignition interlock program is to not allow people to drive after they have been drinking, plain and simple," she said. "To now require ignition interlock devices to be equipped with GPS, or any other technology that can track the program participants' whereabouts, is overreach and may indeed be unconstitutional."

The Department of Public Safety maintains that the devices have proved to be a successful tool in keeping drunken drivers off the road. In a statement, department spokesman Bruce Gordon said the reporting capabilities built into the devices provide "instant notification of a user violation, such as the use of alcohol or failure to comply with a rolling test. It also allows DPS to monitor violations and take necessary action without having to wait 30 days, as was the case previously."

While the "real-time" reporting is now required for all of the devices, Gordon said his department does not use or store the data gathered from them. He said the state also doesn't require the devices to use a specific technology.

"There are five manufacturers certified to provide ignition interlock devices in Minnesota and all five have machines that provide real-time information," he said. "These devices are currently being installed in participant vehicles."

A spokesman for DFL Gov. Mark Dayton said the governor stands by the Department of Public Safety on the issue.

Some lawmakers, however, are not convinced.

Issue of privacy

Lesch said he is frustrated that the Legislature is faced with another question of protecting citizens' privacy, given that the state has dealt with challenges on several related issues in recent years.

He pointed to discussions over data gathered through cellphone tracking, police body cameras and license plate readers.

"I'm extremely surprised we've reached a point where not only were those cautionary tales not heeded, but they were in fact seemingly summarily ignored by initiative to include tracking information with a program that was not in any way intended to go in that direction when it was originally passed."

At least one of the manufacturers of the devices seems to agree.

Smart Start, one of the companies that makes the devices used in Minnesota, filed a lawsuit against the Department of Public Safety this fall over its use of GPS data. The department is currently working to ensure all of the devices are equipped for data collecting and reporting by Jan. 1.

The lawmakers' proposal — for which Lesch said he expects broad support from both Republicans and DFLers — would restrict the Department of Public Safety's ability to track users of the device, and it would return more power to the Legislature to make decisions about policies related to the interlock systems.

Scott said she has already put the issue on her committee's schedule for when the Legislature convenes in January.

Erin Golden • 612-673-4790