"There's a very clear connection between people leaving their cars unattended and running, and motor vehicle thefts," Zalewski said. "The numbers increase when we see that."
He said an ordinance in place in Wauwatosa makes it illegal to leave cars unlocked and running, with the keys in the ignition, on public streets.
The ordinance does not apply to private property, such as a home's driveway, although Zalewski said police discourage that also.
He said stolen vehicles are often used in other crimes.
"By not leaving your car unattended, you can do something to ensure you’re not a victim of a crime and you’re not giving the opportunity to these criminals to get their hands on a new vehicle so they can go wreak havoc elsewhere in the community," Zalewski said.
Many municipalities around the state have ordinances in place similar to Wauwatosa's that cover public streets and areas. Some of those communities include Milwaukee, Kenosha and Germantown.