Blood Test

Blood tests are one of three methods used to determine a driver's blood alcohol concentration level (BAC). Blood tests are the most accurate tests, although a defense lawyer may be able to contest them by arguing the blood samples were not properly preserved or the laboratory didn't follow proper record-keeping and organizational procedures.

Recently the U.S. Supreme Court ruled that police officers must get a warrant before ordering DUI suspects to undergo a blood test. This means if a driver refuses to submit to a blood test after a DUI arrest the police will have to get permission from a judge to draw their blood.

Most drunk driving cases, where the driver has submitted to a blood test, will result in a drunk driving conviction if the blood test indicates the driver's BAC was above the legal limit. As mentioned above, there are times when the evidence provided in court may prove there was an error in the blood draw or preservation of the blood, but generally, blood tests are extremely difficult to disprove.