Challenging or Suppressing a DUI BAC (Breath Test) Result

Prior to your current experience you may have thought that the DUI process was fairly straightforward. You are now discovering that there are twists and turns and you may find yourself checking with your defense attorney to make sure you understand the next step. That is the way of any legal process. But it is a fair bet that there are three parts to this process that you distinctly remember. You remember being pulled over. You remember taking a test to determine your blood alcohol content. You remember being charged. In fact, if you are like many people, you keep replaying all three of those incidents over and over in your mind.

Think about the test that you took. Was it a blood test? Although it is possible – it is unlikely. Blood tests require more paperwork and certification so they are usually not given unless the police suspect the usage of another drug besides alcohol or if you yourself demanded one which is your right. Outside of one of these circumstances, it is more probable that you were given a breath test.

The breath test measures the percentage of ethanol in your blood. The result will be a number that reflects what the test has determined is your “BAC.” Washington has a legal limit that your BAC can be while driving and that is .08.

At first glance that looks fairly scientific and objective and you would think that would erase all questions – if you are at or over .08, you are guilty. That is what many people assume even those who are charged. The problem with this assumption is that the test is not necessarily objective or scientific because the test is not necessarily reliable. There are many reasons for this and the reasons are even greater for the portable breath test. That is why the portable test is voluntary and its results are not admissible in court.

Before the possible causes for breathalyzer malfunction and unreliability are examined in more detail, there are some legal points to understand. No matter what you are suspected of – or even charged with – you still have rights. Police are under certain rules to make sure that your rights do not get violated. Some of those rules regard the protocol and procedures that an officer is required to follow before he can either administer a test or have a test administered. Talk to your defense attorney, give as many details, there may have been a breach of protocol that you were unaware of but your lawyer will know about it. Also, every person that gives the test is required to be certified to do so. Police are people just like anyone else. Have you ever forgotten to get something renewed? Sometimes they do too. Any evidence obtained when regulations were not followed can be suppressed by your Tacoma DUI Defense Attorney.

You are probably now wondering about the scientific reasons mentioned earlier that a breath test might be unreliable. Breath tests supposed look for ethyl alcohol or ethanol which is the form of alcohol found in the blood after drinking alcoholic beverages. This seems to make scientific sense. The problem is that there are other substances that can be falsely read by the machine. Acetone is one of those substances. Some diets can also cause substances which will be falsely read as ethanol. These would be those diets favored by those with diabetes or have other reasons to have a low carb level. These diets cause a bodily process called “ketosis.” Ketosis causes isopropyl alcohol in the blood which the test has been known to falsely read as ethanol.

Any equipment that is not properly calibrated will give a bad performance. Do breathalyzers need to be regularly calibrated? Yes, they do. Is it always done properly? No – mistakes have been made. Does this cause bad readings? Of course it does.

These are just a few examples – there are other possibilities. So if you have been charged with DUI and are facing a bad breathalyzer test result you do not need to think that everything is lost. You need to talk to a Pierce County / Tacoma DUI defense attorney. Call or e-mail The Law Offices of Smith & White, PLLC. Your free case analysis awaits you.