CHICAGO (CBS) –– A Chicago area lawman is out on the streets night after night, hunting drunk drivers, and it is personal.

For one thing, he believes 99 percent of the recent wrong-way crashes on area roads are caused by drunks behind the wheel.

For another, he lost his own daughter in a fatal DUI accident.

CBS2’s Mike Parker reports.

Officer Tony Wasco is a member of the Cook County Sheriff’s DUI unit. He’s seen the aftermath of too many wrong-way crashes.

“You’ve got to vehicles coming at each other at 55-plus miles per hour, you’re going to have a horrific crash,” he tells Parker.

There’s been a rash of wrong-way crashes on Chicago area roadways since December. In one of them, on I-80 near Hazel Crest, a wrong-way driver carrying three friends plowed into another car. He and two of his friends were killed as well as a fourth person in the other car.

CBS 2 asked the sole survivor of that I-80 crash if he believes his driver was intoxicated.

“He was buzzing a little bit,” Eduardo Rodriguez said. “I guess he was drunk.”

In his patrol car, Officer Wasco carries a picture of his 16-year-old daughter, Justina, who was killed in 2006 in a DUI related crash.

“Every night, it reminds me of why I’m out on the roads trying to save a life,” Wasco says.

In recent weeks, the officer has ticketed two wrong-way drivers and luckily caught them before there was harm done. Both had entered two different expressways by heading down the off ramps. Both drivers, he says, were legally drunk.

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