About DUI Testing

Across the United States it is illegal to operate a motor vehicle under the influence of alcohol.  Under the influence of alcohol is determined by the BAC which is the blood alcohol concentration.  The law determined that .08 is the percent deemed under the influence.  Three tests are administered to determine the BAC.

• Breath - The breathalyzer is a portable machine that is connected to a plastic tube.  The suspect must blow into the tube and the machine will determine the BAC based on the alcohol in the suspect's breath.  This is the most common DUI test given. Penalties for refusing to take a DUI test are much stiffer than if the suspet had taken the DUI test and had failed. The breathalyzer can be given by the officers and can also be given at the police station.  There are a few testing errors that can occur, like whether or not the breathalyzer had been properly maintained or calibrated or rather the equipment had a malfunction.    


• Urine - The urine test is the least used DUI test.  The urine test can be used to screen for other drugs. The suspect is required to give a urine sample into a container while carefully monitored in the bathroom.  The chain of custody is strictly adhered to unless there is question whether the urine had been tampered with.


• Blood - Blood tests are considered more accurate than the breath or the urine tests. The officer must take the suspect to a medical facility to draw the blood sample. Blood contamination, switch samples and fermented blood are examples errors of blood testings.