An increasing number of Arizona police departments are using blood samples rather than breath tests to build cases against drunken drivers, making it increasingly difficult for offenders to fight their DUIs.
The Mesa, Chandler and Peoria police departments all use blood tests to gauge a person’s blood-alcohol concentration. And by 2010, the Phoenix Police Department will accept only blood evidence.
“Blood is highly accurate,” said Jeff Thompson, a DUI squad sergeant for Mesa police, which has been using blood tests for nearly a decade. “With breath, there’s no going back.”
The Breathalyzer is a machine, and defendants can challenge whether it was properly maintained and calibrated at the time of their test and whether an officer operated it correctly.
Nearly 1,400 DUI cases in Phoenix and Glendale were dismissed in 2000 after judges upheld challenges to the machines.
Phoenix police wasn’t ready to process large quantities of blood until recently, according to Sgt. Chris Moore, a vehicular crimes unit supervisor.
Since March, about 40 percent of the department has transitioned from breath tests to blood. About 60 officers who have gone through a weeklong training class collect blood evidence at a precinct or inside a DUI van.
“The hope is that (blood) evidence won’t be challenged as much because of its reliability and more people will plead guilty,” Moore said.
The increased use of blood tests for drunken driving comes when the stakes for DUI are at their highest in Arizona. Last month, a new DUI law went into effect requiring first-time offenders to use a device to provide a breath sample to start their car. “Super extreme” offenders, or those with a 0.20 percent blood-alcohol content or higher, will face a minimum of 45 days in jail.
Craig Penrod, a Tempe DUI attorney, said blood evidence is more difficult to refute, but it’s not bulletproof.
Lab technicians do not test the blood, but the alcohol molecules in the air space above it. The accuracy there could come under fire, Penrod said, or when officers draw blood from suspects.