Compared with similar offences two decades ago, defendants charged in DUI cases face emotional objection from the public, increased penalties, and a lack of sophistication in the tools that law enforcement uses to determine if a driver is under the influence. DUI offenders could benefit from a forensic toxicology expert, such as Dr. David Salvage, to ensure that the charges consequences are fairly given. Dr. David Salvage has proven himself in the courtroom as an expert witness in DUI cases in support of primary legal counsel.

The technology used to calibrate Breathalyzers is lacking sophistication causing false results and unnecessary charges. This proves problematic considering the frequency that breathalyzers are used as primary evidence in DUI cases.

In fact, breathalyzers are notoriously unreliable, and controversy surrounds their validity when used in a court of law. Many factors will result in a false result, and usually in a manner that inflates the reading, working against the driver.

For example, if the driver belches, hiccups, smokes a cigarette or uses oral nicotine products like Nicorette gum, or vomits 20 minutes before taking a breathalyzer, BAL limits will be artificially elevated. In most states, law enforcement officers are required to take note of this behavior and to monitor the driver for these actions. If any of these behaviors have been observed to have occurred, the driver should not be tested for another 20 minutes.

Additionally, metabolic factors play a role in how fast alcohol is metabolized. For example, there are patients and ethnic groups with low levels of alcohol dehydrogenase – an enzyme that blocks the breakdown of alcohol. Because of this, they are more likely to have an elevated BAL. This is also true for a variety of other medical conditions including hyperthyroidism, gastro-esophageal reflux disease, as well as many medications including oral contraceptives, H2 blockers such as Zantac, and many types of commercially available mouthwash.

One of the most common problems for people who have recently ingested alcohol is the presence of residual alcohol in the oral mucosa. The rate of absorption of alcohol form the oral mucosa into the bloodstream also varies tremendously between individuals – and for someone who may not be inebriated to the point of impairment, a breathalyzer may give a high false reading because it is detecting blood in the oral cavity and not that which has been absorbed systemically.

Breath temperature can also affect the results. The average breathalyzer used in the field is calibrated to produce the most accurate effects at a temperature of 34 degrees centigrade, whereas the average body temperature at the time of observation has been noted most frequently to be 35.5 degrees. This also results in the BAL being artificially high with the standard equipment being used.

Other factors to consider are the regular inspection and calibration of breathalyzers. These events should be documented to ensure the test results. Law enforcement is advised to videotape field testing to document the degree of a driver’s motoric impairment.

Lawyers defending of drivers charged with driving under the influence should seek the advice of a forensic toxicology expert, like Dr. David Salvage, who can determine whether a defendant was intoxicated or if faulty calibration or test error resulted in an elevated BAL reading.

Dr. David Salvage is an expert witness and a board-certified forensic psychiatrist who is experienced in DUI cases. Contact him for a consultation to discuss your client’s specific needs.

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