COURT WATCH: Expert Witness Gives Confusing Testimony during DUI Trial on Legitimacy of Officer Using Field Sobriety Test on One-Eyed Man

By Avery Redula 

WOODLAND, CA – A misdemeanor jury trial proceeded here in Yolo County Superior Court Wednesday, with a man charged with driving under the influence and driving without a license.

The jury was expected to retire late Wednesday or Thursday to decide the guilt or innocence of the accused.

The hearing has outlined concerns with the field sobriety testing, faulty new technologies used to test sobriety (NVR Systems), lack of body camera footage, and no microphone audio from officers who responded to the scene.

The defense has raised concerns about the accuracy and legitimacy of a California Highway Patrol officer using the field sobriety test of HGN, the horizontal gaze nystagmus test, because the accused only has one eye.

Not only does the accused only have one eye, which questions the accuracy of the HGN test, claimed the defense, but Tuesday’s hearing revealed the accused was nervous in the presence of law enforcement as a person of color, which affected his demeanor toward officers and possibly affected his field sobriety tests.

Wednesday’s hearing heard testimony from a criminalist who was permitted to act as an expert witness. This criminalist gave conflicting accounts upon direct and cross-examination on the legitimacy of the CHP using the HGN test on the accused to check for sobriety.

Deputy District Attorney Aimee McLeod called this criminalist as an expert witness because the witness is an expert specifically on the correlation between alcohol and its effect on the human body, alongside testing for blood alcohol content (BAC) in blood and urine samples.

However, in addition to asking about blood samples, DDA McLeod decided to also ask the witness about field sobriety tests used by officers.

Under DDA McLeod’s direct examination, the expert witness said there are three standard field sobriety tests as outlined by the National Highway Traffic Safety Administration, or NHTSA. This includes the HGN test that was used by a CHP officer the night of the incident.

DDA McLeod asked the expert witness if officers are allowed to administer the HGN test to someone who only has one eye. The witness states, “Yes, I believe so. But the officer now needs to understand they now only have three clues as opposed to six.”

The witness explained these clues include checking pupil size, if the subject is able to smoothly move their eyes, and if they are able to track the object held by the officer. These three clues for checking sobriety are doubled to six to account for both eyes.

During Tuesday’s hearing the CHP officer said through the HGN test he could see the accused’s eye “bouncing.”

But, Deputy Public Defender India Neville’s cross-examination put the legitimacy of using the HGN test as a tool for measuring the accused’s sobriety into question.

DPD Neville asked the expert witness, “A look into equal pupil size and equal eye tracking is needed for the HGN test to be used. Correct?”

The expert witness confirmed that both eyes are needed to fully complete the HGN test and evaluate sobriety, but mentioned that the jerking motion of one eye could possibly be used to move forward with a chemical test.

DDA McLeod also questioned the expert witness by exhibiting a lab report she produced on the results of the accused’s blood test. The accused was reported to have had seven beers the night of the incident between the hours of 6:30 and 10:00 p.m., and was subsequently blood tested the following morning between 8:10 and 8:20 a.m.

The expert witness testified the accused’s blood sample demonstrated a blood alcohol content (BAC) of 0.118 percent with a 0.005 percent range of uncertainty through utilizing the headspace gas chromatography blood testing method (the standard blood testing procedure of the Department of Justice).

She also testified that this result would be the subject’s BAC at the time of the test in the morning, not the BAC at the time of the alleged incident.

DPD Neville subsequently cross-examined the witness about what blood tests look for, asking the expert witness to confirm that the blood test only tests for alcohol content, which the expert witness confirms.

“So the headspace gas chromatography does not test for gamma-hydroxybutyrate, or GHB. Also known as the date-rape drug. Is that correct? It only tests for alcohol?” DPD Neville questioned.

DDA McLeod could be heard commenting to Judge Daniel Wolk about DPD Neville bringing up GHB.

“I am not quite sure how this can be introduced as evidence. It is extremely speculative and has absolutely no evidence anywhere to back it,” DDA McLeod stated.

About The Author

Avery Redula is a second year at UC Davis studying English. After undergrad she plans to attend law school, where she can pursue criminal law. She is most interested in cases regarding domestic violence and gang violence, as she learned from her summers spent at the DA's office that they are issues that most affect her home county of San Joaquin.

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