Tiny Clues Are Big Factors in Hit-Run Cases

A broken windshield wiper and a shard of plastic. Those were the clues police were left with to determine who killed 13-year-old Alina Zapata.

The eighth-grader was walking back from a movie last Sunday night in Buena Park when a truck driver barreled through a crosswalk, hit her and hurled her nearly 50 feet. The driver sped off and, two days later, Alina died.

With no eyewitnesses, the police -- as in thousands of hit-and-run cases in California each year -- must blend sophisticated technology, forensic science and old-fashioned detective work to track the vehicle and driver.

There were 99,747 hit-and-run accidents in California in 2002, 268 of them fatalities. While authorities could not provide data, officers say they solve a relatively high number of hit-and-run cases.

The clues are often meager -- paint chips, shattered glass, tire marks -- but they are often enough to help police solve the cases. Forensics and technology are used to reconstruct the scene, allowing investigators to determine precisely what happened. Chemicals that illuminate even the most minuscule speck of blood are used on suspect vehicles.

For Buena Park investigators, the crime scene was far from ideal. The rain had pounded hard that night, washing away potentially valuable clues.

There were no tire tracks. No glass. No visible paint residue from the vehicle. Even Alina’s shoe, which could have helped investigators determine the speed of the truck, had been knocked around in traffic, ruining it as evidence.

And of the nine calls officers received in the days to come, none has led to a suspect. All they know is that it was a truck and that it was light-colored.

“It’s not like ‘CSI’ where everything’s perfect when you get to the crime scene,� Don Beilke, an accident investigator working on the case, said, referring to the popular television show.

Several law enforcement agencies -- including the Orange County Sheriff’s Department, Irvine Police Department and the California Highway Patrol -- reconstruct collision scenes using three-dimensional computer programs.

“It allows us to document the scene relatively quickly and analyze things without tying up traffic,� said Orange County Sheriff’s Deputy Jeff Guyer, an accident investigator.

While the computer program allows investigators to determine how an accident might have happened, it is the clues investigators gather at the scene that will help police find the driver.

Warren Clark, who has worked on hit-and-run cases for 30 years and teaches criminal justice at Cal State Long Beach, said one thing that can easily solve the case is the license plate. Drivers, speeding off to avoid police, often don’t realize they’ve left behind the most incriminating clue, he said.

Most of the time, the clues are not so obvious. A good tire mark, found on the street or the victim’s body, can help police find possible vehicles and tell the vehicle’s approximate speed. The absence of skid marks, as in Alina’s case, is a sign that the driver didn’t try to avoid the collision or slow down afterward, Clark said.

Shattered glass from headlights have codes embedded inside that help police focus on a particular vehicle.

Sometimes, the impact of a collision is so severe that flakes of paint are embedded in the victim’s clothes.

Buena Park investigators said they have sent Alina’s clothing to the Orange County sheriff’s forensics laboratory in the hope that forensic scientists will turn up a fleck of paint and determine its origin.

If a chip of paint is found, scientists can melt it down, and, once it’s in a gaseous form, it can help determine the vehicle’s manufacturer, said Gary Jackson, senior forensic specialist in Orange County’s laboratory.

Once a suspected vehicle is impounded, forensics experts can match the evidence to the vehicle.

But in the toughest cases, such as the one in Buena Park, where clues are scarce, the public can be the investigators’ best hope.

“Oftentimes a break in a case like this will come from tips,� said Buena Park Police Sgt. Jim Banks. “Somebody who knows the driver -- or the driver himself may feel some guilt and decide to turn [himself] in.�