The Alco-Sensor IV, a DUI breath testing device, has been in use by The San Francisco Police Department since 2001. But Public Defender Jeff Adachi and District Attorney George Gascon say the department's 20 sensors have not been properly maintained since at least 2006.
"Results we have here plainly show accuracy tests were not being done," Adachi said.
Adachi and Gascon say police calibration and accuracy logs show page after page of columns with the same result when there should have been a difference.
"This seemed not only peculiar, but a mathematical impossibility," Adachi said.
"They were doing the calibration; had they actually done the second portion, the accuracy, they would have had a variant," Gascon said.
This now throws into question hundreds, if not thousands of San Francisco police DUI convictions where the sensor was used. Adachi and Gascon are reviewing cases and the SFPD has stopped using the devices and has its own investigation underway.
Gascon became police chief three years after it appears the bad testing began and says there's no way he could have known what the small unit of two testing officers were doing.
"It's impossible, even for myself or for Greg Suhr or Heather Fong previously, or any of the other chiefs, to have necessarily have knowledge that there was a failure to follow procedure here," he said.
Gascon says though many cases could ultimately be dismissed, the breath test is only one piece of evidence in a conviction.
For now, the SFPD is using the same field sobriety tests commonly used by all law enforcement.
The public defender has set up a hotline for people with DUI cases who might be affected by the bad breathalyzer situation. Here's the criteria:
Convicted of DUI in SF Superior Court
Arrested by SFPD officer
Given a preliminary breath test at the time stopped
Represented by the Public Defender's Office
Otherwise, contact your private attorney