Why Do Police Destroy DUI Evidence?
Posted by Lawrence Taylor on October 13th, 2008As we all know from watching TV, the police are always very careful to preserve the evidence in criminal investigations. Except in DUI investigations.
What is the single most important piece of evidence in most drunk driving cases? The Breathalyzer test. In fact, it’s the ONLY evidence of the crime of driving with over .08% blood alcohol. And it’s pretty important for the “driving under the influence” charge, too: the law presumes the defendant is under the influence if the test result is .08% or higher. Evidence just doesn’t get more important than that.
So, of course, the police are careful to preserve the breath sample, right? I mean, there may be some question later of whether the machine was working correctly; it would be a simple matter to save the sample so it could be tested again on another machine. And, hard to believe, but the defense may not want to just take the officer’s word that he administered the test correctly and that the test results were from the defendant.
Unfortunately, the breath sample is routinely destroyed moments after it is tested.
But how can this be? That’s a question that was asked a few years ago by a defendant in California appealing his DUI conviction. The Court of Appeals of that state agreed and reversed the conviction:
Due process simply demands that where evidence is collected by the state, as it is with the Intoxilyzer, or any other breath testing device, law enforcement agencies must establish and follow rigorous and sytematic procedures to preserve the captured evidence or its equivalent for the use of the defendant. People v. Trombetta, 142 CalApp.3d 138 (1983).
How hard is it to save the defendant’s breath sample for later retesting? The Court noted that a “field crimper-indium encapsulation kit” was readily available, cheap and approved by the California Department of Health Services. So why isn’t the evidence saved in DUI cases today?
The Trombetta case was appealed by the state to the United States Supreme Court….where it was reversed:
Whatever duty the Constitution imposes on the States to preserve evidence, that duty must be limited to evidence that might be expected to play a significant role in the suspect’s defense. To meet this standard of constitutional materiality, evidence must both possess an exculpatory value that was apparent before the evidence was destroyed, and also be of such a nature that the defendant would be unable to obtain comparable evidence by other reasonable means. Neither of these conditions is met on the facts of this case. California v. Trombetta, 467 U.S. 479 (1984).
What? Neither of these two conditions is met in a DUI case? Let’s take another look at the Supreme Court’s test…
1. The possible value of the defendant’s breath sample in helping prove innocence was not apparent before it was destroyed…..What? The machine never makes mistakes? It was not apparent to the police that a re-analysis of the all-important breath sample might be of any value to the suspect?
2. The defendant was able to “obtain comparable evidence by other means”…..How? He has no access to another breath test. At best, he might be able to get a blood test at a hospital, if the police let him — but it would probably be so much later that it would not be relevant or even admissible in court.
Another example of “The DUI exception to the Constitution”.
It’s interesting that the New Hampshire Supreme Court later rejected the Supreme Court’s reasoning, and relied upon its own state constitution in requiring breath samples to be saved:
A suspect would face numerous practical difficulties in obtaining a second sample on his or her own. While in police custody, the suspect would have to locate an available, licensed technician capable of promptly performing a second test, no matter what time of day or night. Even if a defendant successfully obtained an independent second test, the results would not have the same evidentiary force as would a second test performed on the same machine at approximately the same time. Opinion of the Justices, 557 A.2d 1355 (1989).
The Trombetta decison was, as intended, a huge green flag to police agencies across the country: Go ahead and destroy the main evidence — but only in DUI cases. And law enforcement agencies have happily complied.



It’s unbelievable that police, in any criminal matter, would be allowed to get rid of the one piece of incriminating evidence. Were this a murder trial, rape or some other crime, people would absolutely be livid over such conduct.
Why do police destroy evidence ? In my opinion there are two reasons. #1- The police have the opportunity and the ability to do so. #2- We do nothing and let them get away with it, when and if they are caught. The double the penalty law is a good law and should be passed.
http://www.reportbadcops.com/
Larry,
The state has other reasons why they can’t just save the breath in a balloon and let us re-test it.
Although the law talks about ”.08 grams of alcohol per 210 liters of breath”, they aren’t interested in full liters of breath, or even a full breath. All they are testing for is the peak breath level, which they tend to find at the end of an exhalation.
In their calculations, the machines are programmed to disregard the early part of the exhale, which will tend to be lower than the later part. In fact, the Intoxilyzer 5000 machine, still being used in Virginia, but soon to be phased out, actually watches the BAC as it rises during the exhalation, and then takes the peak BAC, once it levels out. Any lower BAC seen earlier in the sample is ignored, and this is considered normal by the programming.
Common sense would suggest that they would take the entire breath, and then calculate an aggregate BAC for the entire breath. Of course, common sense doesn’t apply in DUI enforcement.
Paul McGlone
pmcglone@mcglonelaw.com
McGlone Law Firm
4118 Leonard Drive
Fairfax, VA 22030
703-273-2750
My answer to why police destroy DUI evidence is based on real life experience;
Answer; because the dui evidence police gather can show the “Malfeasance” and civil rights violations, which open a personal lawsuit towards the Police officer and his family including the police agency, and even the DMV.
In my case the police video alleged DUI evidence was “lost, stolen, or destroyed” which would have shown “Malfeasance” by law enforcement, (a public servant on a private citizen), including the “Malfeasance” of the CHP officer (s) which was the impetus of why I refused to speak, only answered with the word “no” and invoked my 4th and 5th Amendment rights. By the way there was two CHP units with two Video recordings from each police vehicle.
My Alleged DUI evidence was so damning to police officials that it simply did not exist according to the CHP and would have allowed me to sue the CHP, and the DMV,
Instead it all stopped in court with a plea of no contest to a non alcohol related traffic offense. The DMV upheld the suspension for my refusal absent a court conviction, based on hearsay written on a police report by a malfeasant CHP officer.
That is one reason why police destroy Alleged DUI evidence.
I have proof from the DMV of my impeccable perfect safety professional driving record, now I have a bogus document from the DMV that says my license is suspended for allegedly refusing a chemical test. Had the DMV got to review my alleged DUI evidence provided by the CHP my refusal would have been set aside.
Now I can’t drive, my driving history is perfect, I have no criminal record, and because the police destroyed this most important evidence they get to punish me for their “Malfeasance”
It makes absolutely no sense, absolutely none.
Good news is the fatal bus crash driver up in Sacramento was not DUI. But the police arrested him anyway for some trumped up violation regarding his license ….? Remember how the CHP, the media, and the public jumped the gun and already convicted the driver absent “Due Process’?
There needs to be better more realistic DUI laws in this country. And it’s up to the Defense Lawyers to make it happen and Mr. Taylor is doing a great job getting the ball rolling,
Thank you Mr. Taylor for listening, and your blog too.
Everyone try to have a great Holiday Season and don’t go near a vehicle even if you’ve had a thimble full of alcohol…….