Drunk Driving Chemical Tests

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DUI testing - Once the officer determines there is probable cause to conclude the driver is under the influence, he or she will arrest the driver and transport him or her to the jail for a chemical test. Many jurisdictions offer the driver the choice of a blood, breath or urine test (some jurisdictions only offer blood and breath). Your attorney should be familiar with each of these tests and will investigate the following factors in order to challenge the case in court:

Blood test

Was the blood drawn within the time specified by law? Was the blood drawn by a person certified by the state or county? Was the proper amount and type of preservative used in the blood vial? Was the blood properly stored prior to the test? Is there a sample available for the defense to test independently? Are the officials, procedures and machinery used in the
test all certified by the state or county?

Breath test

When was the breath machine last calibrated? Was the machine serviced just before or after the test? Have the machine and the operator been certified by the state or county? What calculations does the machine use in order to convert air alcohol to blood alcohol? Is the machine subject to outside interference from nearby electronic equipment? Did the driver belch or burp prior to taking the test (brings up alcohol)? Did the driver use mouthwash or breath spray (containing alcohol) before taking the test?

Urine test

Did the driver completely void his or her bladder before he gave the urine sample? Did the driver wait the required time before he gave the sample? Was the sample properly stored prior to testing? Is there a sample available for the defense to test independently? Are the officials, procedures and machinery all certified by the state or county? These questions will go a long way in putting a dent in the prosecutor’s case.