Forensic Expert Testifies in DUI Case

by Marshall Hammons

In Department 16, in front of Judge Rene Navarro, expert witness Michael D. Laufer took the stand in a misdemeanor driving under the influence case where the defendant is accused of having both alcohol and a small amount of amphetamines in her system at the time she was pulled over.

The assistant district attorney’s questions first focused on the expert’s qualifications as a forensic toxicologist and certifications. Dr. Laufer has a certification from the California Department of Health, has co-authored several peer-reviewed journal articles on the effects of drugs on humans, and has been qualified over 58 times as an expert witness. He started his career as a forensic toxicologist by focusing on alcohol, but over his eleven and a half years has expanded his expertise to include other drugs. This includes methamphetamines. The defense then asked a few other questions, such as the fact that the majority of Dr. Laufer’s authorship was focused on cannabis, not meth. The expert responded that he wrote his thesis on the topic of meth. Judge Navarro admitted Dr. Michael D. Laufer as an expert witness.

The A.D.A. then went on to technical questions regarding the effects on the human body from alcohol and methamphetamines. The A.D.A. asked questions about alcohol as an intoxicant. Dr. Laufer explained that alcohol use leads to both a mental and physical impairment. These mental impairments include memory issues, reduction in inhibitions, reduced ability to follow directions, and reduced ability to multi-task. The physical impairments include increased reaction times, reduced muscular and motor control leading to a lack of coordination, and a decreased ability to balance due to the effects on the inner ear.

The signs of intoxication, such as slurred speech, lack of memory, or inability to balance, are all present themselves at varying levels at varying times depending on the person. For example, one person has a beer and feels sleepy, while another may start having difficulty balancing. The expert then explained that noticing these is signs is dependent on the person looking. For example, friends at a bar might only notice the impairment when their friend gets up, walks to the bathroom, but wobbles back and forth while walking. Other people, such as a trained officer, may be able notice these effects sooner.

Alcohol significantly impairs complex, divided-attention tasks. The expert explained that driving is a complex, divided-attention task. A complex, divided-attention task is a task that requires lots of decisions to be made over both mental and physical tasks. Driving falls into this description because it takes motor control to keep the steering wheel in line, gas or brake pedal depressed the correct amount, and other physical movements needed to keep the car moving in the right direction at the right speed. One’s mental focus is highly strained; Dr. Laufer explained that attention is split between distractions on the interior of the vehicle as well as important items of focus on the outside of the vehicle. The distractions inside the vehicle could be music or talking, various lights, or one’s phone. The important items of focus outside the vehicle include other cars, road signs, and pedestrians.

The expert explained blood alcohol content (“BAC”) as the ratio of alcohol to blood. Dr. Laufer used the example of a bathtub. The larger the bathtub, the more the amount of alcohol would need to be poured in; likewise, the larger the person, the more alcohol required to raise the BAC level. The type of alcohol, someone’s sex, and their weight all effect BAC levels. The A.D.A. tried to ask a hypothetical question that mirrored the characteristics of the defendant, but Deputy Public Defender Nitin Sapra objected. The Court sustained this objection. The BAC level is also affected by the rate of elimination. Elimination is the rate at which alcohol dissipates from the blood. Elimination rate is dependent on several factors, but sex plays a large role as women dissipate the alcohol faster than men.

The expert then turned to methamphetamines, or “meth.” Dr. Laufer explained that meth is a central nervous system stimulant. The effects in lose doses are increases in energy and concentration. However, in larger doses, there is an immediate euphoric effect followed by a manic episode that can last for a few hours to several days, depending on the amount taken. Generally, paranoia and hallucinations can also accompany meth use when done for prolonged periods of time. The elimination of meth involves effects similar to morphine; the user experiences lethargy and sluggishness both mentally and physically.

Dr. Laufer explained how meth is taken. It can be taken orally, such as in a form of a pill, smoked, or injected. Injecting or smoking the drug puts the drug directly into the bloodstream, whereas taking meth orally still has to make it through the stomach and digestive tract. The liver then breaks down meth into amphetamine, or “amph”. Amph is also an active compound, meaning that it also effects the user. Amph is used in Adderall and other medications. The ratio of meth to amph can show that the user took just meth and it has been broken down into amph, or, if the ratio is close, that the person took both individually.

During this explanation, Deputy Public Defender Nitin Sapra made objections as to the questioning by the A.D.A. Judge Navarro overruled these objections quickly, almost without considering them.

Dr. Laufer then went on to explain how alcohol and meth interact. The expert said that if someone is drunk and takes a small amount of meth, it is somewhat like having a double espresso; there is a slight increase in alertness, but that is accompanied by an increase in inhibitions. However, if drunk during the crashing phase, the reduced mental and physical abilities are compounded. If the user is drunk and has a large amount of meth, that creates an interaction leading to rapid-appearing, but sluggish, thoughts and much more erratic motor control.

Dr. Laufer then explained how these signs and symptoms are detected. The first test is a field sobriety test (“FST”). An FST measures direction following, physical impairment, and mental impairment. An FST does this by creating a divided-attention task, such as balancing and counting. Another test is the horizontal eye nystagmus (“HEN”) test. This measures the twitching of the eye as it tracks an object; someone who is not intoxicated would track the stimulus smoothly whereas an intoxicated person would involuntarily twitch their eye back and forth. Dr. Laufer explained that a sober person could exhibit signs of impairment even though sober if they were one of the rare cases of eye twitching, or has a pre-existing physical or mental impairment. Other signs and symptoms include smelling oder, seeing the person walking with an unsteady gate, and overall confusion.

The expert then explained the testing procedures and calibration of the machines. The American Board of Forensic Toxicology (“ABFT”) certifies the machines and provides calibration and control test data to the lab in San Francisco. The expert also explained the chain of custody of these samples.

Deputy Public Defender Nitin Sapra objected several times during this convoluted explanation due to the expert’s lack of personal knowledge on the exact process used by the ABFT, but this frustrated Judge Navarro. Judge Navarro, in front of the jury, overruled these objections and told Mr. Sapra to review several California Evidence Code sections. Upon review, some of these did not even seem to apply to the circumstances of the case. Closing arguments are to be presented this week.

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About The Author

David Greenwald is the founder, editor, and executive director of the Davis Vanguard. He founded the Vanguard in 2006. David Greenwald moved to Davis in 1996 to attend Graduate School at UC Davis in Political Science. He lives in South Davis with his wife Cecilia Escamilla Greenwald and three children.

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