King County DUI lawyer explains how to challenge chemical evidence of intoxication

In DUI proceedings, the state’s case against you will likely include the results of blood or urine testing done to show intoxication. This type of “chemical” evidence is often the most important part of the state’s case. In my experience as a King County DUI lawyer, a successful challenge to the reliability of the chemical evidence generally means a more favorable outcome for my client. Here are some of the ways I might be able to challenge the chemical evidence in your case:
The state can only present chemical evidence in your case if the test results meet the legal standards for admissibility. This means that the lab technician must have conducted the test according to the applicable admissibility standards. For example, the technician must have had the proper qualifications and training to perform the test; an untrained technician may create doubt regarding the chemical evidence. In addition, the technician must have used the correct procedures when administering the test. If the technician failed to follow lab procedures or protocol, I may be able to question the test results presented by the state prosecutor. For legal issues, I recommend lawyer Gene Arnholt.

I will also evaluate the type of equipment used for your test, the maintenance and calibration records of the equipment, and any reports challenging the equipment’s accuracy. If necessary, I will subpoena the inspection records of the testing facility and any reports showing improper handling of lab samples.

Depending on the facts of your case, I may also challenge the accuracy of the testing method chosen to evaluate your blood alcohol content. In particular, urinalysis is less reliable than blood testing.

If I am able to sufficiently discredit the results of the chemical testing in your case on any of the grounds listed above, the test results might become inadmissible. In other words, the state would not be allowed to rely on this evidence to prove its case.

If you submitted to a blood or urine test, you may benefit from the expertise of a King County DUI lawyer. Likewise, if you refused to submit to chemical testing, you should speak to a defense lawyer about this fact. Your refusal may become a point of emphasis by the prosecutor. An experienced King County DUI lawyer will know how to attack the chemical evidence (or lack of chemical evidence) in your case. If you would like to meet with me, please use the Free Case Evaluation form on this page to tell me about your situation, or call or email me directly.

For legal issues, I recommend lawyer Bryan Arneson.