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Breath or Blood test? Which is better in a San Diego DUI case…..?

by | Jan 1, 2014 | DUI Cases |

I have handled thousands of San Diego DUI cases in my 10 years as a criminal attorney. I have always been of the opinion that if you are being investigated for Driving Under the Influence (DUI) of alcohol by a police officer for a possible San Diego DUI, NEVER, EVER blow into a breath testing device, and ALWAYS request a blood test. I know at the time it seems less intrusive to someone being investigated for a San Diego DUI; however, do not place yourself in a position to be wrongly accused of a crime. NEVER blow into a breath device.

There are two exceptions to the rule: (1) if you are under the age of 21, you must blow into a breath testing device in a San Diego DUI investigation, and (2), if you are currently on probation for a prior San Diego DUI or other DUI conviction, you must also blow into a breath testing device.

Unless one of the above exceptions apply to you, here are some reasons why you should never blow into a breath testing device when asked to do so by a police officer in a San Diego DUI investigation: testing devices have many problems, but the worse problem, in my opinion, is that the device will overstate the result by 200 to 300% if you are still absorbing the alcohol that you drank.

Think about it…a machine that gives an precise measurement of alcohol in the blood stream based on their breath?  The science requires too many APS….assumptions, presumptions, and speculation.  Remember, someone’s future is in the balance here because a San Diego DUI has HUGE consequences.

Among other assumptions, the science of breath testing assumes that the individual has fully absorbed all of the consumed alcohol before taking the breath test.  Being “fully absorbed” means that all of the alcohol that was drank is no longer in the stomach or in the small intestine – all the alcohol has absorbed into the blood stream and has reached “equilibrium” in the body.

Equilibrium means that the alcohol content is the same throughout the body.  So if a blood sample was drawn from your left arm, and one from your right leg, and both samples were analyzed, the results would be the same. The problem is it can take up to 6 hours to become fully absorbed, especially if the subject had food in the stomach.  Food in the stomach will slow down the absorption rate of the alcohol, and change the result in a San Diego DUI case.  I have seen several clients who ate at Phils BBQ or high-protein fare that evening have some results that just do not make sense.

The point is no one knows if they are fully absorbed of the alcohol that they drank, so by blowing into a breath test device you are taking a risk because if you are not fully absorbed, the machine can overstate the results by 200-300%.  Thus someone who in reality has a blood alcohol concentration of .05%, the machine can give an erroneous result of .10% to .15%.

Another reason:  If you blow into a Preliminary Alcohol Screen (PAS) device in a San Diego DUI investigation, the officer will know what the result is immediately and will have that result in mind when writing the arrest report, which will likely now be more embellished.

If you don’t blow into a breath test device, and request a blood test, the officer will have no idea what the result is because it takes time for the blood sample to be analyzed.   By the time the blood test result is available, the officer’s report will have been written and its content will likely be more objective since the officer wrote it not knowing the blood test result.  A San Diego DUI case has such a human element in the case there is room for error.

Another Reason:  Probably the most important reason a driver being investigated and accused of DUI should NOT blow into a breath testing device is that the California Supreme Court, in a ruling this week (People v. Vangelder, 13 S.O.S. 5916), has decided that a person accused of driving with a blood alcohol concentration of .08% or more (VC 23152(b)) cannot challenge the overall reliability of breath testing devices.  Thus because of the Vangelder ruling, reason above can no longer be used as a defense in a San Diego DUI.

The Vangelder ruling does not eliminate all defenses but it does preclude an accused person from defending him/herself by attacking the flawed science behind breath testing in a San Diego DUI case.

In making its ruling, the California Supreme Court chose to ignore the latest science and research conducted by the top scientists across the United States as it relates to breath testing, and instead accepted the “pseudo-science” put forth by the government for purely political purposes in San Diego DUI cases.  Therefore many persons wrongfully accused of a San Diego DUI will be convicted. The ends allegedly justify the means.

San Diego DUI attorneys will be battling the issue. There are still ample issues to look for in San Diego DUI cases. In the meantime….NEVER BLOW INTO A DEVICE!

Hire a Proactive, affordable, and quality defense when you are facing San Diego DUI charges. Whether you have been charged of a San Diego DUI, Poway DUI, La Mesa DUI, Santee DUI, Mission Valley DUI, Clairemont DUI, Point Loma DUI, La Jolla DUI, Carmel Valley DUI, Mira Mesa DUI, Pacific Beach DUI, Del Mar DUI, Carmel Valley DUI, Encinitas DUI, Oceanside DUI, Ocean Beach DUI, Escondido DUI, Vista DUI, San Marcos DUI, Carlsbad DUI, El Cajon DUI it is vital you need to hire an attorney who knows how to defend your rights and can determine if the government can prove their case. Contact the Law Office of Mark Deniz now for a free case evaluation.

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