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Forced Blood Tests in DUI Cases


For a suspect arrested for a DUI in California, the law requires that the police inform them that they have no right to refuse to submit to a breath or a blood test and that if they refuse to submit to a test, the refusal may lead to enhanced penalties including a longer license suspension and jail time if convicted. A DUI suspect may choose a breath or a blood test, unless one of those tests is not available, in which case the suspect must consent to the remaining test.

This occurs most frequently if a person is injured and taken to a hospital. In this case, it is not practicable to take a breath sample and a suspect is required to submit to a blood test. In addition, if a breath machine does not work for whatever reason or a suspect is unable to blow sufficient air into the machine to reach a reading, the suspect must then consent to a blood test.

If a suspect refuses to submit to a test, the police may use reasonable force to take a sample of blood. This may involve restraining and handcuffing a suspect to a chair. Even though the results of the blood test can then be used to prosecute a person for driving with an excessive blood alcohol level, the refusal may also be used by the DMV to enhance the length of suspension for a DUI arrest, and by the court to enhance penalties for a conviction.

If the case goes to jury trial, the jury would also be instructed by the judge that the refusal may be seen as evidence against the defendant as showing “consciousness of guilt”.

The LAPD, CHP and local Los Angeles Police Departments do not normally use force to take a blood sample without consent. They prefer to just charge the suspect with a DUI based upon the rest of the evidence and cite a “refusal” to the DMV and Court. Some police departments in Orange County routinely force blood tests on uncooperative suspects and prosecute based on the refusal and the results of a forced blood test. These cases can be the most difficult to defend for DUI Lawyers in Orange County as we have to deal with the results of the blood test plus the consequences of the refusal.