Twin Cities car thieves beware: Soon, there'll be almost no place to hide.

The Ramsey County Sheriff's Office and several east metro police departments will soon join the ranks of local police agencies using license plate readers to help catch car thieves. The devices have become a popular tool to fight auto theft in recent years, even as debate about possible privacy infringements heats up.

Agencies in Minneapolis, St. Paul, Washington County, Hennepin County and several other jurisdictions are already using the readers.

"We are kind of coming in late to the party," said Randy Gustafson, spokesman for the Ramsey County Sheriff's Office. "We're doing it because it's a very effective way of finding bad guys."

The office is drafting a policy to determine guidelines for using the readers, which automatically scan license plates and alert police to whether a vehicle is stolen or if the owner has an active arrest warrant, Gustafson said.

The sheriff's office and police in Maplewood, Mounds View, New Brighton and White Bear Lake plan to get readers that should be operational by mid-February, he said. The devices have already been purchased.

Ramsey County averages more than 3,000 auto thefts each year.

In Minneapolis, where police have used readers since 2008, auto thefts dipped 14 percent last year — to about 1,600 — from the year before.

"It truly is an incredible law enforcement tool," said John Elder, police department spokesman.

Ramsey County is buying the readers as part of its Auto Theft Prevention Collaborative Initiative, which is designed to combat auto theft by working on detection, prevention and apprehension. A $115,000 grant from the state Department of Commerce will help pay for the devices, auto theft prevention brochures and bait cars.

Gustafson said that establishing a policy for how data obtained by the readers is used and retained is especially important in light of recent local and national debate surrounding police use of surveillance technology. It hasn't been determined how long data gathered by the readers will be retained, he said.

Nicole Norfleet • 612-673-4495

Twitter: @stribnorfleet