Are DUI Urine Tests Reliable?
Under New Mexico’s implied consent laws, a driver must submit to chemical testing after being lawfully arrested by an officer who has probable cause to believe that the driver was operating a motor vehicle while under the influence of alcohol. It is up to the arresting officer to decide which method of chemical testing to use – breath, blood, or urine.
If you are pulled over for a DUI and offered a choice of which test to take, always arrange for an independent blood or urine test to compare to the State’s breath test machine.
What Makes Urine Testing Less Reliable than Other Methods?
The purpose of chemical testing is to determine the driver’s blood-alcohol content. The percentage of alcohol in a person’s urine at any given time will probably not be the same as the percentage of alcohol in their blood.
Many experts agree that the urine alcohol level is approximately 1.33 times the blood alcohol level, but this is an average that may not be applicable to the case at hand. An experienced DUI defense attorney can produce studies showing that some people have up to 50% less alcohol in their blood than in their urine, and that the difference can vary widely from case to case.
The physical facts about how the bladder functions are another reason urine testing is often considered to be unreliable. Urine is stored in the bladder and remains there until the bladder is emptied, so the percentage of alcohol in the contents can depend on what was consumed before or after the alcohol and whether or not the bladder has been emptied.
For example, if a driver consumed a large amount of a nonalcoholic beverage before consuming alcohol without emptying their bladder, the alcohol in the urine would be diluted by the nonalcoholic beverage and the results of the urine test could be misleadingly low. On the other hand, a driver who consumed alcohol and then waited several hours before driving could have misleadingly high urine test results if the bladder was not emptied after the alcohol was consumed.
DUI Defense in New Mexico
If you have been charged with a DUI after urine testing in New Mexico, contact our office as soon as you can. We will meet with you for a case consultation, free of charge, and explain your options, as well as what we can do for you.
Remember that a DUI charge is not the same as a conviction. Our experienced DUI lawyers at New Mexico Criminal Law Offices are well versed in many DUI defenses, including the flaws inherent in urine, blood, and other types of chemical testing. Our firm has a history of successful case results defending clients against criminal charges throughout New Mexico, and you can depend on us for outstanding DUI defense.