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A provision of the California Vehicle Code known as implied consent mandates that drivers who are lawfully arrested for a DUI / DWI must take a chemical test in order to determine their blood alcohol content (BAC).
When drivers refuse to submit to chemical tests, police are authorized to take blood samples by force – either by holding the driver down, or by threatening to do so. During a forced blood draw, trained medical personnel draw the blood for use in the later prosecution for drunk driving.
The United States Supreme Court decided the forced blood draw issue in the landmark case of Schmerber v. California in 1966. This case held that it is permissible for the police to take a warrantless taking of a person’s blood for the purpose of chemical testing to determine intoxication, provided that the taking of the sample is done in a medically approved manner, after a lawful arrest, and based upon the reasonable belief that the person is intoxicated. If these guidelines are followed, then a forced blood draw does not violate the Fourth Amendment right against unreasonable search and seizure.
Because of the temporary nature of alcohol in the blood, courts have ruled that it is unreasonable to require a warrant to draw someone’s blood in a DUI / DWI case. Opponents believe that a forced blood draw is an invasion of privacy, a violation of the right against self-incrimination, and an act of violence.
In California, a forced blood draw is considered a “refusal.” A refusal has many repercussions, including fines, jail time, and suspension of driving privileges. Therefore, a forced blood draw may result in both a conviction for DUI and added penalties. Some police agencies have a tendency to state that a DUI suspect refused even when he or she did not. Some common issues include misunderstandings resulting from language barriers, overreacting police officers, or drivers who fear needles.
In order to withhold the forced blood draw results, a suppression motion may be instituted. A suppression motion is a motion usually made before the start of trial, where the court is asked to exclude evidence because it was not gathered in a constitutionally valid way.
As mentioned previously, the Supreme Court stated that the proper protocol to be followed in a forced blood draw. If this protocol is not followed, then the DUI defendant may validly claim a violation of his or her Fourth Amendment right. Thus, it is not only proper, but mandated, to suppress this evidence. Suppressed evidence may not be considered by the judge or heard by the jury. According the legal principle of “fruit of the poisonous tree,” any evidence gained as a result of the unconstitutional evidence must also be suppressed.
This is a serious and necessary weapon in the fight for constitutional rights, and one of the few safeguards the law offers where a person’s rights have been violated. An experienced DUI / DWI defense attorney can review the procedures used in a forced blood draw to determine whether a driver’s rights have been violated. If the proper protocol was not followed, the attorney will argue that the evidence should be repressed.