Arizona DUI cases almost always involve a chemical test. There is a movement in Arizona towards the exclusive use of blood testing. It is well settled that blood testing is more accurate than breath testing. But how accurate is blood testing? Can it truly determine a person's blood alcohol concentration? I believe that these are reasonable questions to be asked by a person accused of DUI and facing 30 to 45 days in jail.
Under our system of justice we should demand better answers from the government than "because we said so" or "because our lab has the highest standards." Simple conclusions are not good enough in science and they should not be good enough in justice.
So who checks the government's test results in Arizona? The simple answer is the government. They merely claim to check themselves. I have yet to see one Arizona crime lab that conducts blind testing by an independent party.
Here is how the actual process works. In Arizona DUI cases, The government expert will tell juries that they do double check their work. That is, they have a quality assurance program to make sure the blood alcohol test results are accurate. But the government's oversight of their work is not what you my think. Instead retesting every sample, or randomly retesting a portion of the samples, the lab merely does a technical review.
A "technical review" is not retesting. The Government toxicologist usually puts between 30 to 40 blood samples into a blood tester. Then they turn the blood tester on and leave. The blood tester commonly runs overnight and the printed results are reviewed by the government lab person.
This review of the printed documents is what is known as a technical review. The actual documents are called chromatograms. They are simply pieces of paper with graphs and data on them (retention times, area counts, etc...) If the run has the usual 30 to 40 samples there could be well over 100 pages of data.
In court, the government will tell the jury that they "double check" all the tests. What they actually do is take those 80 to 100 pieces of paper and give it to another employee of the same lab. That person then reviews the data. As long as the data appears to be consistent, they conclude it is an accurate test. In Court, they tell the jury they got a second opinon from another analyst to ensure the accuaracy of the tests.
A nationally recognized expert, Dr. A.W. Jones, has opined that in forensic testing of blood samples retesting should be done, not a mere a "technical review." It is his opinion, that a mere technical review is inadequate to ensure the accuracy of the test results.
This standard makes perfect sense in DUI cases because the level of punishment is often dependent upon the test result. If a person's blood alcohol concentration result is .165 the person is facing a minimum of 30 days in jail. If he was under a .150 then he is merely facing 1 day in jail. Is it too much to ask the government to check their work when 29 days of jail is at stake? I guess the answer depends on how important the result is to you.
If you were at the doctor and she said "the blood tests were back," "we need to operate," let's "prep for the mastectomy." Most people would seek a second opinion. Why...because the issue is too important to merely rely on the first test. When it matter to you - you retest.
P.S. I will address the Defendant's ability to do their own retesting in my next entry.