DAVIS, Calif. -- Scotland Yard investigators were stumped. A bouncer had been stabbed to death in the alley outside The Paradise Bar in South London. Pools of blood were left behind by the victim, the suspect and someone -- or something -- else.
"They swabbed the blood up off the floor, they extracted DNA from it," explained Marcia Eggleston, a researcher at the University of California, Davis. "When they typed it, they couldn't get a result."
Turned out it was animal blood, something few crime labs are equipped to analyze. So Scotland Yard turned to the Internet and tracked down the Veterinary Genetics Laboratory at UC Davis and its extensive database of animal DNA.
The lab's verdict: The blood matched a bull terrier which was found to belong to a man who had been kicked out of the bar.
The finding helped put the killer in prison for life.
The lab's technicians, who work out of a small, nondescript building and several trailers on the Davis campus, most often test animal hair, which works best if it's pulled out at the root. But they also extract DNA from urine, saliva, feces, dead skin, dander and just about anything else.
Forensics isn't the lab's main job. About 98 percent of its work is DNA typing to determine the bloodlines of horses. Since 1995, the lab has typed 600,000 horses.
Saved two dogs
About six years ago, the lab branched out into criminal work when a Simi Valley woman who owned three great danes called. One of her dogs had bitten a neighborhood boy's arm. She wanted to euthanize only the dog that had attacked.
"They heard that UC Davis did animal testing, so they were hoping we might be able to do something," Eggleston said.
The dog had left a saliva trail on the boy's shirt sleeve, which the lab matched to one of the swabs the woman had scraped on the inside of all three dogs' cheeks.
"We went, 'Wow, this is kind of cool,'" Eggleston said.
It's the more serious cases that are most rewarding.
A few years ago in rural Chickasaw County, Iowa, a Mennonite woman was gardening with her toddler and the family dog when a man arrived in a pickup truck. He got out, accosted the woman, dragged her to his truck and tried to rape her, according to Doug Strike, former chief deputy for the Chickasaw County Sheriff's office.
"We arrested him," Strike said. "But she couldn't pick him out of photo lineup, nor could she say this was the truck."
But the woman had seen the dog, a border collie, urinate on the man's truck tire. Strike tracked down the Davis lab.
"We thought, 'Why not try it?' ... and it just worked out beautifully," he said.
The suspect ended up pleading guilty to attempted sexual assault.