DUI Blood Testing Overview
Of the three chemical tests that are used by police to measure BAC levels, the blood test is the most scientifically reliable. It’s also messier and more invasive. In some breath test jurisdictions, whenever a suspect refuses to take a breath test, the police officer has the option of obtaining a search warrant and forcibly taking the suspect’s blood. Other jurisdictions, such as Montana, do not allow forcible extraction of blood under any circumstances.
A lab technician will analyze the sample. The police must keep a detailed record (called a chain of custody) of the sample’s whereabouts. The sample must be stored securely in proper temperatures or the validity of the result will be compromised. For a blood test result to be admissible in court, an expert must testify that all the procedures were strictly complied with, otherwise the sample will be excluded and deemed scientifically unreliable.
Some states, such as Florida, have mandatory blood seizure statutes. Such statutes allow the police to draw blood regardless of consent so long as probable cause and causation requirements are met – i.e., so long as the police have probable cause to believe the person was DUI and caused an accident that resulted in death or serious bodily injury to a human being (including himself). States that permit mandatory blood draws often grant police the right to use reasonable force in obtaining the sample. What is deemed to be “reasonable force” may vary from state to state.
Who may draw your blood, where it’s drawn, and under what circumstances the draw can be made varies significantly from jurisdiction to jurisdiction. In some states, a blood sample will not be taken unless an accident with serious bodily injury occurred. Other states will allow blood to be drawn when a breath test is impracticable or impossible. Extremely conservative states, such as Arizona, allow blood to be drawn in any DUI case at the officer’s discretion. Whether and under what circumstances blood may be requested and drawn is a legal issue that should be discussed with an experienced attorney familiar with the particular laws of your jurisdiction.