Motion for Blood/Urine Sample to be Split

The experienced DUI / DWI defense lawyers at The Kavinoky Law Firm perform a great deal of work before a drunk driving case ever goes to trial. A skilled defense attorney typically makes one or more pretrial motions at the driver's arraignment or at a later date. One motion common in a driving while intoxicated case is a request to have a blood or urine sample split so that it can be tested by an independent forensic expert.

Individuals arrested for drunk driving or driving under the influence of drugs (DUID) must be told of their right to have a blood or urine sample preserved for independent testing. This is especially important when a driver submits to a breath test to determine blood alcohol content (BAC), because when a breath test is taken, there is no independent sample retained for later retesting.

A chemical test is a significant piece of evidence used against the defendant. The prosecution will attempt to use a chemical test result of .08 percent BAC or greater - the legal limit for driving in all 50 states - to prove a defendant is guilty of driving while intoxicated. However, many chemical tests are administered hours after the driver was last behind the wheel. Remember, it's not illegal to have a BAC of .08 percent at the police station, only while driving a vehicle. An independent defense expert may be able to establish that the driver's BAC at the time of driving was below the legal limit.

When the split is obtained, it will be sent to a private, independent forensic lab for testing. Law-enforcement agencies are required to collect a sufficient amount in order to allow future tests. Testing will analyze not only the blood alcohol content of the sample, but will also determine whether proper testing protocol was followed.

Police must follow strict guidelines when conducting chemical tests. Blood samples should be drawn using sterile, dry hypodermic needles and syringes, or using clean, dry vacuum type containers with sterile needles. No alcohol can be used to clean the skin or the equipment used in the collection. The blood must be mixed with a precise mixture of anticoagulant and preservative. If the levels of the anticoagulant and preservative are not correct, the test results can be skewed. For example, if the blood sample becomes fermented, it will produce falsely high BAC readings.

In some cases, the driver's blood or urine sample is lost or destroyed. While the prosecution has no legal duty to collect evidence that might be beneficial to the defense, they do have an obligation to preserve this possibly exculpatory evidence - evidence that may point to the defendant's innocence. If the prosecution neglected to preserve such evidence, a savvy drunk driving lawyer will ask the court to issue sanctions that may result in suppression of the evidence or the dismissal of the case.

If the prosecution doesn't comply with a court order to split a blood or urine sample for independent analysis, the defense can ask for sanctions against the prosecutor, and the evidence the prosecutor would have used to convict the defendant may be excluded. If police have failed to preserve a sample, then this will be the basis not only for exclusion, but possible dismissal of the charges.

However, in order for sanctions to be levied, the defense must prove that the prosecutor or police acted in bad faith. If bad faith cannot be established, then the defendant is entitled to relief only on a showing that the evidence was material and exculpatory.

Drivers accused of DUI / DWI often believe that a chemical test result that places them over the legal limit for driving means an automatic conviction, but that's not necessarily true. A California defense attorney who focuses on driving under the influence cases will file a motion to have any sample split and sent to an independent laboratory to determine whether the driver's BAC result can be challenged.