Non-Compliant Breathalyzer Used in DUI Case

By Hannah Grayson

A DUI trial reconvened on its second day Monday morning in Department 14. It was found that the breathalyzer used to determine blood alcohol content was not compliant with California code.

The prosecution continued the questioning of Officer Anthony Zill of the California Highway Patrol. He proceeded to go through documentation proving that the device in question had passed accuracy tests.

In the cross-examination, it was confirmed that the breathalyzer was not compliant with Title 17 of the California Code of Regulations which lays out the procedures in which to collect breath, blood, and urine for evidence. This device does not take into account the presence of mouth alcohol, which can inflate the blood alcohol content. The device used at the station reads an error if mouth alcohol is detected.

The prosecution then called its next witness and expert, Natashia Shaw. Shaw is a criminalist with the San Francisco Police Department focusing on breath alcohol. She is in charge of maintaining and testing the breath alcohol devices used at the station once a person is brought in. These devices are equipped with mouth alcohol detectors.

In cross-examination, the defense focused questioning on the effects of unabsorbed alcohol. Shaw confirmed that unabsorbed alcohol does not cause any mental and physical impairment. She also confirmed that the rate of absorption is unpredictable and varies depending on the person’s metabolism.

Shaw calculated, using the blood alcohol content gathered at the CHP station, that in order for the defendant’s blood alcohol content to be below the legal limit at the time of driving, she would have to have approximately two or three unabsorbed standard alcoholic drinks in her stomach at the station.

The prosecution had both witnesses estimate the presence of mouth alcohol based just on the data of blood alcohol content provided. Both witnesses said mouth alcohol did not appear to play a factor. The defense, however, dismissed this as speculation as the two experts were not involved in the gathering of the data at the time of arrest.

The defense is basing its argument on the fact that the defendant had just had the shots of Hennessy right before she began driving. This would lead to alcohol remaining in the mouth at the time of the breathalyzer test and, as they argued, causing the blood alcohol content to be higher than what it truly was.

They also argued that the alcohol was only absorbed after the defendant was arrested and taken to the CHP station. This accounts for her blood alcohol content level being above the legal limit using the Title 17 compliant device.

After Shaw’s testimony, the prosecution rested and the trial ended for the day. It is scheduled to resume on Tuesday.

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About The Author

The Vanguard Court Watch operates in Yolo, Sacramento and Sacramento Counties with a mission to monitor and report on court cases. Anyone interested in interning at the Courthouse or volunteering to monitor cases should contact the Vanguard at info(at)davisvanguard(dot)org - please email info(at)davisvanguard(dot)org if you find inaccuracies in this report.

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  1. Bill Marshall

    There are crucial elements missing here… obviously a novice ‘reporter’… sloppy reporting… unless the practice of law by the DA has really changed…

    I say this as a juror in  similar case many years ago.

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