San Francisco DUI Lawyer California DMV Hearing Attorney

• Introduction
• What To Do First
• Elements of the Offense
• BAC Calculator
• Misdemeanor DUI Case
  • Investigative Considerations
  • Miranda Warnings
  • Pretrial Motions:
    • Suppress DUI Evidence
    • Motion for Discovery
    • Pitchess Motions
    • Blood Sample Motion
    • Motion to Strike Prior
    • Miranda Violations
  • Plea Bargains
• Criminal Jury Trial
• Criminal Court Punishment
• Alternative Sentencing
• Sentencing Enhancements
• Refusal Cases
• Felony DUI Case
• Medication Cases
• Drug Cases
• Federal DUI Case
• Out-of-State Drivers
• Drowsy Driving
• Post-Conviction Relief
• Ignition Interlock Devices
• Motorcycles, Boats, Planes
• California Highway Patrol
• California DUI Resources

Blood Sample Motion

In a California criminal DUI trial, a defense attorney may introduce a number of pre-trial motions before the case ever gets to trial. All of these motions, if successful, will aid the defendant and the defense lawyer by suppressing evidence and/or statements that may harm the defendant’s case, providing more information about the prosecution’s case, making it possible for an independent expert to analyze chemical test results, or allowing the attorney to learn more about any complaints made against an arresting officer.

One common pre-trial motion is a request to have a blood or urine sample split to allow independent testing by a forensic expert.

Police are required to tell anyone arrested on suspicion of Driving Under the Influence (DUI), or Driving While Intoxicated (DWI), of the right to have a blood or urine sample preserved for later re-testing. This is particularly important when the driver agrees to a breath test, because there is no independent sample retained for later retesting.

Chemical test results is a significant piece of prosecution evidence. The prosecutor will use a test result of blood alcohol level at or above the legal limit to prove the defendant is guilty of driving under the influence (DUI). However, many chemical tests are administered an hour or more after the driver is pulled over. It is not against the law to have a blood alcohol content (BAC) of .08 percent or greater at the police station - only when behind the wheel. An independent expert may be able to establish that the driver's blood alcohol content at the time of driving was not above the legal limit.

If the motion to split a blood or urine sample is granted, the split is sent to a private, independent forensic toxicologist for testing. Independent testing will analyze the blood alcohol content (BAC) and determine whether proper testing procedures were strictly followed.

Chemical test samples must be gathered under strict protocols. Blood samples must be drawn with sterile, dry hypodermic needles and a syringe or a clean, dry vacuum type container. No alcohol can be used to clean the skin from where the specimen was taken or the equipment used in the collection. Additionally, the blood must be mixed with a white powder comprised of an anticoagulant and a preservative. If the levels of the anticoagulant and preservative are not correct, the results of the tests may be invalid.

In some DUI cases, the original blood or urine sample gets lost or destroyed. While police and prosecutors are not required to collect evidence that is beneficial to the defense, once the evidence is collected, they have a duty to preserve it. If the prosecution fails to preserve that evidence, a skilled San Francisco drunk driving lawyer will ask for sanctions which may result in the exclusion of the evidence or the dismissal of the case.

If police have failed to preserve a sample for future analysis, then this will be the basis not only for exclusion, but possible dismissal of DUI charges.

However, for such an action to be taken, the defense attorney must prove that the prosecutor or police officer acted in bad faith. If no bad faith can be established, then the defendant is entitled only to recognition that evidence that may have pointed to his or her innocence has been lost.

A chemical test that shows that a driver had a BAC of .08 percent or greater doesn't mean an automatic DUI conviction. A San Francisco DUI attorney who concentrates on DUI defense will move to have the sample split, send it to an independent laboratory, and create reasonable doubt in the defendant's guilt.

Home > Bay Area DUI > Misdemeanor DUI Case > Pretrial Motions > Blood Sample Motion