![](https://davisvanguard.org/wp-content/uploads/2016/01/YoloCourt-16-765x510.jpg)
By Olivia Biliunas
WOODLAND, CA – In a misdemeanor trial here in Yolo County Superior Court last week, California Highway Patrol officer Robert Martell was closely questioned by the defense on the accuracy of an alco-sensor device used for preliminary alcohol screening (PAS) in DUI investigations.
The accused allegedly was parked on the side of the I-5 freeway fixing his car’s flat tire when an officer pulled over to assist. After suspecting the driver was intoxicated, the officer administered certain diagnostic tests, and utilized the alco-sensor device. After the tests, the driver was arrested for a DUI.
Deputy Public Defender Danielle Craig questioned Martell, who is in charge of overseeing the various testing modalities to assess potential driving under the influence/DUI cases.
Martell was asked about Title 17, a regulatory measure to ensure device accuracy, and the discrepancies seen during three different testing dates. Officer Martell maintained there could be many reasons for the device to require three testing samples rather than its two standard samples.
Within Title 17, the tests need to be within 0.02 of each other to be admissible, as Martell clarified to the court.. DPD Craig asked him if a 0.05, another 0.05, and a 0.06 difference would be admissible. He continued to state there could be many reasons why the test needed more than two readings.
DPD Craig responded, “something wonky was going on” to which Officer Martell finally deviated from his repeated static response and claimed he did not know why the test results were outside of the span of 0.02, noting it could be human error, not blowing right into the device, or police officer error.
After DPD Craig brought up the discrepancies in the testing surrounding the dates in which the accused underwent a DUI investigation, the question as to why the device required an additional test still remained.
From there on, DPD Craig asked the officer if there was a log recording all of the documented tests from which the device was used. The officer said no, but that the test data is stored on the device and that Deputy District Attorney Aimee Carrrazco never asked for the data.