Crime lab uses evidence to tell a story, solve crime
By Sophia Fischer sfischer@theacorn.com

Entering the Ventura County Sheriff's Department Forensic Sciences Laboratory is like walking onto the set of "CSI: Crime Scene Investigations," except this is real.

The blood samples being analyzed are from real people; the evidence being examined under hightech microscopes comes from actual crime scenes.

To enter the laboratory at the Ventura County Government Center, visitors need prior permission and a visitor's pass, and they must be accompanied by a staff member. Inside, 30 full-time scientists work on about 8,000 cases each year, providing law enforcement throughout the county with evidence evaluation and analytical testimony for criminal investigations.

The multiroom, cliniclike facility is divided into separate areas: controlled substances, breath alcohol, DNA, firearm and tool marks, trace evidence, and the property and instrument rooms.

Kristin, a scientist in the trace evidence section who, like some of the others in the lab, only gave her first name, was examining tire tracks from a crime scene to identify the vehicle involved. Using photos of different types of tire tracks, she was able to determine the make and model. Her department also investigates evidence such as footprints, adhesives, knots and fibers to determine if a suspect was present at the scene.

A photo on the wall of a paper clip and fingernail prompted the scientists to tell the story of a case where a man claimed he had not been at the scene of a burglary. A tiny swab from under his nail revealed a bit of chocolate cake from the counter of the home that had been broken into. The suspect said he ate the dessert at a local restaurant. The lab obtained ingredients from both cakes and found that different starches were used. The starch in the cake from the crime scene matched that found under the suspect's fingernail. That piece of information led to a guilty verdict.

In the instrument room, powerful microscopes analyze evidence, such as layers of automobile paint to determine the type of vehicle. Forensic scientist Paul Crowley, who often testifies in court on behalf of the lab, demonstrated how a nanogram, one-billionth of a gram, of a substance can be analyzed with a special machine to identify a drug.

"Just from a tiny sample we can identify all kinds of things," scientist Matthew Berger said.

The controlled substances section of the lab analyzes liquids and solids. Scientists can identify a substance based on its reaction to the addition of certain chemicals. Berger pointed out a photo of pink methamphetamine crystals. Meth crystals are usually clear, but lab tests revealed what caused the color—a strawberry powder for flavoring milk available in the grocery store, probably used to sweeten the drug, Berger said.

In the blood alcohol area are roadside instruments that police use when they stop drivers suspected of being under the influence of a controlled substance. Ventura County was the second county in California to obtain the hand-held devices. The shelves are lined with Breathalyzers, each numbered and named after the characters in the "SpongeBob SquarePants" television cartoon.

"It's a lot easier than memorizing the number on the back of the instrument," Berger said.

In determining blood alcohol levels, scientists measure the air in a tube above the small collected sample.

Bodily fluids from sexual assaults and DUI cases are held in refrigerated storage from six months to one year.

In the DNA section, scientists identify bodily fluids and who they came from. Special machines and chemicals are used to separate proteins, lipids, fats and carbohydrates from pure DNA. Examination of drops or pools of blood left at crime scenes can reveal the point of impact and from what direction it came.

In the firearm and tool marks area, examiners study objects used as weapons or try to determine what was used.

"Anytime a hard item hits a soft item it's considered a tool," said a scientist named Jeff.

Using a comparison, or double, microscope, Jeff was able to simultaneously examine two bullet casings from one crime scene, determining that they were shot from the same gun. In another case, scientists were able to refute a suspect's claim that he shot the deceased victim, who he said was on top of him, in self-defense. From the way the bullet hit the victim in the chest and back, scientists determined that the weapon—and suspect—were about 15 feet away, refuting the suspect's testimony.

In the property room, thousands of pieces of evidence are stored on overflowing shelves: suitcases, skateboards, clothing, toys, blankets—some of it wrapped in brown paper and labeled. Freezers are filled with perishable items.

"If we don't need the item we return it to the owner, auction it or destroy it," said Tammy, who oversees the property room. But if it's needed, she said, "We have to keep the stuff for 99 years if it's a known suspect; forever if it's not a known suspect."