Yolo County residents are getting behind the wheel under the influence of drugs at a troubling rate. Nearly one of every two arrests in the county for driving under the influence involves drugs – legal and illicit, according to the District Attorney's Office.

Now, Yolo prosecutors say they have the tools to stem the tide.

The Yolo County District Attorney's Office recently received $248,000 in state Office of Traffic Safety grants to form a unit dedicated mostly to prosecuting motorists impaired by drugs and investigating DUI collisions. The prosecution team of one investigator, one attorney and support staff will work on cases from the arrest through the court phase.

Yolo County's is one of 20 such district attorney's offices, including Sacramento and Calaveras counties regionally, to form such a prosecution unit to follow drug-impaired driving cases, according to the Office of Traffic Safety.

The strategy gives prosecutors an advantage in the courtroom, said Chris Cochran, an Office of Traffic Safety spokesman.

Without a team, Cochran said, DUI cases often are passed from one prosecutor at an arraignment to another at trial to yet another at sentencing, none of whom is especially well-versed in DUI law.

With a team approach, "it puts them on equal footing with a good DUI defense lawyer," Cochran said.

Meanwhile, an investigator specially trained to spot drug impairment can help bolster a case, leading to a conviction.

Matt DeMoura, a Yolo County deputy district attorney, leads the team and expects to be busy. The grant money will allow his team to prosecute 76 of the office's 101 DUI cases. Of those, 48 cases – 63 percent – involved suspected drugged or drugged and drunken drivers.

"It's surprising the number who have drugs on board," from prescription drugs and ill-gotten medicines to marijuana and street drugs, DeMoura said.

A survey released last week by the state's traffic safety office shows just how pervasive the problem is.

Based on late-night tests of 1,300 drivers who agreed to roadside testing in nine California cities in August and September, the survey showed 14 percent of the participants tested positive for drugs that may impair driving. About 7 percent tested positive for alcohol.

Drilling deeper, illegal drugs were found in saliva samples from nearly 5 percent of drivers, the survey revealed.

"These results reinforce our belief that driving after consuming potentially impairing drugs is a serious and growing problem," Christopher J. Murphy, Office of Traffic Safety director, said in a statement announcing the findings.

Meanwhile, more Californians are expressing concern over drugged driving. More than 95 percent of Californians said driving under the influence of drugs was either a "very big problem," or "somewhat of a problem," according to the survey.

And, the traffic safety office, citing National Highway Traffic Safety Administration figures, said a full 30 percent of drivers killed in crashes in 2010, had legal or illegal drugs in their systems.

Still, prosecuting drugged driving cases is problematic – largely because California has no impairment level for anything but alcohol.

"With alcohol, it's black and white – 0.08 (blood alcohol content) or higher and you're gone," said Jonathan Raven, the county's chief deputy district attorney. "But with drugs, it's much different."

Office of Traffic Safety officials also cite under-reporting of drugged driving incidents, saying instances are not often recognized in the field and testing is costly.

But DeMoura says his unit can draw more attention to the dangers of drugged driving and keep impaired drivers off the streets.

"We want to make people aware that DUIs are not just alcohol-related," DeMoura said. "Hopefully, by getting out there through prosecution, we'll have resources in place to prevent that type of behavior."

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