A common misperception of blood alcohol testing is that the results of
the prosecution's test cannot be challenged in court.In reality, a skilled
DUI defense attorney who understands both the law and science behind forensic
alcohol analysis can do just that.
In many courts, including Scottsdale Municipal Court, blood testing is
conducted using a process known as headspace gas chromatography.This technique
is designed to ascertain the level of ethanol in a person's blood
by measuring that amount of alcohol floating in the air above the blood
sample in a sealed vial.Before the "headspace gas" is measured,
the test vials are prepared using another machine referred to as a pipetter
which is expected to measure precise amounts of blood and another solution
into the test vial.If either of these liquids are introduced into the
test vial in an improper amount, the test results could be effected.
Reliable blood alcohol testing also requires that the blood be collected,
preserved and handled appropriately prior to the testing process.For example,
the collection tubes used by the police are supposed to have both an anticoagulant
and a preservative pre-packaged inside the tube prior to use.These agents
are designed to prevent the blood from clotting and/or decomposing.Even
though forensic scientists have repeatedly established that the presence
of either decomposition or clotting can artificially increase the results
of an alcohol test, police crime labs typically do not conduct any testing
to verify that the anticoagulant or preservative is present in the blood sample.
There are many other nuances to blood alcohol testing that must be addressed
in order to effectively challenge a blood test in a DUI case.Given Arizona's
extreme DUI laws which can mandate a 45 day jail sentence based on a blood test result
alone, it is crucial to have the blood test evidence in your case scrutinized
and challenged by a knowledgeable and experience DUI attorney.
If you have questions about blood alcohol testing in you case, please contact
DUI attorney Joshua S. Davidson today to schedule a free initial consultation.