St. Petersburg Mayor Bill Foster interrupted last week's mayoral forum with an important public service announcement: Don't leave your keys in the car.

No, really.

The plea came in the middle of a discussion on crime, with Foster noting that good police work can't overcome people's lack of common sense.

"Sixty percent of the auto thefts that we have in the city are caused by people leaving their keys in the car," Foster said.

The problem is so bad, city officials say, that the Police Department created a sassily named mascot Willie Everlern to help spread the message to residents. In a black-and-white video , Everlern is shocked to discover that his car was heisted after he left the keys inside while he walked into a convenience store.

We wondered if the situation in St. Petersburg can actually be this bad.

Lo and behold, it’s worse.

Out of the 551 cars stolen so far this year, 460 of them had keys either in the ignition or elsewhere in the vehicle, Police Chief Chuck Harmon said. That’s 83.4 percent.

"If I were a car thief, I’d move to St. Petersburg," said Frank Scafidi, spokesman for the National Insurance Crime Bureau, when told of the numbers. Scafidi said the percentage might be a "high-water mark" in the country.

Over the past several years, car technology has made vehicles harder to steal with screwdrivers and other tools. Many new cars have transponder keys , which means someone can’t unlock or start the car unless the key fob is close to the vehicle. As a result, St. Petersburg has seen a 70 percent drop in auto thefts over the past decade, Harmon said.

As a result, people leaving their keys in their cars has become an increasing source of car thefts in the city. The thefts are crimes of opportunity, so 96 percent of cars are recovered later where the thief ran out of gas. Most area offenders are not trying to bring cars to chop shops or resell high-end models. People are just capitalizing on careless driver mistakes.

According to the National Highway Traffic Safety Administration , 40 to 50 percent of auto thefts nationwide are due to keys in the car.

Just lock your cars, people. As Harmon said, "It’s not rocket science."

One other note: It’s technically illegal to leave your car unattended and running. So not only do you run the risk of having your car stolen, the police could issue you a ticket.

Our ruling

Foster said that 60 percent of car thefts occur because the owner left keys inside the vehicle. In St. Petersburg this year, it’s actually 83.4 percent. An expert said that might be tops in the country.

The specific number aside, Foster’s point that many auto thefts can easily be avoided is 100 percent on the mark. We rate this claim True.