A state representative is planning to introduce legislation next week that would force police to show, in detail, how they use license plate tracking technology.

Rep. Mary Liz Holberg, R-Lakeville, said Friday she has authored a bill that would require law enforcement to disclose where they use car-mounted and stationary license plate readers.

Those readers, which log location data on every vehicle they spot on the road, are being used increasingly by local cops to catch criminals in real time.

That sensitive data, largely documenting the whereabouts of innocent people, is currently public under state law. Lawmakers have already introduced legislation that would reclassify it as non-public.

Holberg said it is important to keep a check on how police use the technology, particularly since she thinks license plate readers are a precursor to local use of facial recognition software.

“We’re going to making all of this data non-public, then where’s the accountability factor?” Holberg said. “How does the public know how you’re using these?”

The bill is not very specific right now, she said, but would at a minimum require agencies to post the locations of their stationary cameras online – Minneapolis has refused to disclose that information. It could also, she mused, require agencies to reveal where they had scanned more than 10 plates.

“Did they run 1,000 plates at the high school, the gay bar and the ‘no tell’ motels?” Holberg said. “Or were they at the country club and the health club?”

The legislation will be introduced next Thursday. “It’ll get the conversation started,” Holberg said.