Blood Result: If the "machine" is the answer, prosecutors and judges need to adhere to ISO and legal predicates.

 Most prosecutors and many defense lawyers hinge their analysis of a DWI case on the blood result. Fact is I don't.  I look at the "totality of the circumstances."  Every blood test can be fought.  It is the State's burden of proof to show the result met all ISO standards, is accurate and the defendant's blood.  If the blood is not going to make a difference (for example the citizen looks highly inebriated and the driving facts are bad) then going to trial and fighting the blood result may not be in my client's best interest.  Here is an example (true life example) of why one should never trust the blood result.  

1.  It may not be the client's result.  How often does this happen?  It is impossible to say because most defendants have some ethanol in their system and no police department calling the lab to say it was a mistake.  A Collin County municipality's police procedure is to have the police officer take a blood test if the cop was involved in a fatality.  When one such police officer, clearly sober, took the blood result it came back he was intoxicated.  Clearly,  this was an error, so the police department called Texas DPS- Garland to apprise them of the mistake.  The lab proceeded (no received notice to the police department before their phone call) to correct the situation.  The police officer's blood result belonged to someone else. How often does this happen to citizens?  How do you catch it?  The identity of a sample is critical.  Despite Texas DPS- Garland's protocol and lab certification, the result was reported. See below the picture of a gas chromatograph carousel (I took this while actual sampling blood).  It is not simple or what most people think.  The original client's blood tube is not put into the machine.  A small amount of the client's blood, along with many others, is pipetted into a new test tube which goes on a carousel that is then put into the machine.  If the new tubes are not identified properly,  the batch results are out of order and incorrect. It is then that someone else's results are reported.  Our clients don't have the privilege of a police department calling in to correct the mistake.  

2.  Most prosecutors place 100% trust in the machine while not being able to explain  how the machine produces a result or how a margin of uncertainty is created.  They are misguided in trusting the laboratory's accreditation.  ISO standards (baseline minimum standards) do no allow a prosecutor to assert a result is accurate because it came from a certified lab (in my experience this is their chief argument).  Laboratories generally apply, pay a fee and receive certification upon an audit (which may last a few days).  This audit in no way encompasses every test on every day.  ISO standards require a machine goes through a method validation before being put into use.  "Garbage in, garbage out" is the old saying.  One cannot rely on the results if the machine was not properly validated.  Tarrant County in my experience (Daubert hearings and arguments) routinely disregard this important baseline step allowing in an unsupported result.

3.  Margin of uncertainty. Texas law does not permit a blood test into evidence unless accompanied by a margin of uncertainty.  This is because a blood ethanol result is an estimate, not 100% by any means.  For an estimate to be accurate, the laboratory must account for differences in scales, balances, pipettes, auto diluters, refrigeration temps, etc.  The margin of uncertainty is hearsay unless the State produces the formula for which they attained uncertainty.  This formula varies greatly from lab to lab. My experience is most lab analyst are unfamiliar with the supporting data or formula for the margin of uncertainty.  Many refer to it as "computer programmed".  This is unacceptable. Our United States Supreme Court has ruled both in Bullcoming and Smith v. Arizona the actual analyst who determined the margin of uncertainty (it's been my experience this is a different employee 100% of the time) must be subject to cross examination and confrontation (6th amendment right) on this calculation. Judges must be suppressing the entire blood test result (as the law requires a margin) where improper predicate is laid on uncertainty.

This is just a primer on a few of the practical issues which are relevant in DWI blood testing.  

For more information see https://www.mimicoffey.com or give me a call.