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Forensic Lab Certification and DUI Charges

Posted by Terry A. Wapner | Sep 25, 2013 | 0 Comments

The most accurate method to determine a person's BAC is a blood test.  Whenever someone is arrested for drunk driving in the state of California, they will be required to choose to submit to a blood or a breath test.  If you choose blood, is the result really that accurate?  And if not, what does it mean for drivers charged with DUI in California?

It may surprise you to learn that in some situations, the forensic lab where your blood sample is analyzed can be the weakest link in your case.  In the state of California, forensic laboratories used to detect BAC levels run the gamut, from state-of-the-art and equipped with highly accurate testing equipment, to outdated labs using methods that can produce inaccurate results.

When your BAC is given by one of these labs, they don't give a very important detail next to the BAC number.  Every estimate of your BAC could be off by a certain percentage, and that percentage varies depending on the exact way your blood was tested, as well as other factors.

Now, if your BAC reads as .09%, to within plus or minus 5 percent, you'd definitely be above the legal limit.  But what if you had that same reading and the test used was only accurate to plus or minus 20 percent?  Now, the test may have gotten it wrong-your levels may have actually been below the limit.

Without seeing this plus-or-minus number (which we call the “measure of uncertainty”), it's impossible to know the range your BAC could have actually been.  Many of California's labs don't meet international certification standards yet, and won't include this number.

While the state is trying to get its labs internationally certified by the end of the year, some may lag behind, and new issues may crop up with the tests used in these labs.

It's one of the best reasons to get an attorney who specializes in DUI defense in California, instead of taking all kinds of cases. DUI attorneys make the effort to keep up with the scientific and technical developments in these labs-lawyers trying to do all types of criminal cases won't be able to give DUI the same level of attention and care.  I am one of those attorneys.  I have spent a great deal of time to learn how to operate the same scientific machines the labs use here in CA.  If you have a DUI with a blood result, call me, Terry A. Wapner.  I can help you.

About the Author

Terry A. Wapner

Terry A. Wapner confines his practice to the defense of persons accused of driving under the influence of alcohol and/or drugs, and related crimes.


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