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Urine Samples and DUI


It is rare now to see a urine sample given following a DUI arrest. If a suspect is detained for DUI based on alcohol, the choice of test is blood or breath. The methodology of analysing alcohol in a urine sample has long since been discredited. Providing a urine sample is no longer an option. In DUI cases based on drugs, the police normally request that the suspect consent to a blood test.

Occasionally, the suspect is given the option of submitting to a urine sample instead. If a choice is given, the advantage of submitting to a urine sample is that it is practically impossible to perform an accurate quantitive analysis of the amount of drug in the suspect's system at the time of the sample. It is only possible to perform a positive or negative test. This leaves the prosecution without a scientific method of quantifying the amount of drug in the defendant's system at the time of driving, and with practical difficulties in proving impairment.

Part of the problem is that urine is a waste product. Urine pools in the bladder and it may remain in the bladder for hours before the person uses the bathroom. For this reason, the amount of a drug in a urine sample is not representative of the amount of a drug in a person's blood at the time the sample is given, and a correlation with impairment is scientifically impossible. It is just an indication that the the suspect took that drug at some time in the past.

The lesson to be learned is that if you are arrested for DUI based on drugs and not alcohol, request a urine test! If you have any questions concerning DUI defense in Los Angeles please call DUI lawyers Gold and Witham for a free case evaluation.