How Can I Challenge my Blood Alcohol Test Results in Court?

You might find it surprising, but there are many ways you can challenge a blood alcohol test in court. There are three main ways blood alcohol content (BAC) is measured aside from field sobriety tests.

Urine Test

Urine tests are considered to be the least accurate out of the three ways to test BAC. Alcohol in urine is 1.33 times the level in blood, so the rule of thumb is to divide the result by 1.33. This, however, can be argued is a too generalized approach for every person when people can differ biologically. Urine tests can be challenged also because of equipment failures, administration issues, chain of custody issues, and failure to substantiate evidence in court.

Blood Test

The blood test to determine BAC is considered the most reliable way to determine BAC, although not infallible. It is tough to challenge this, but it can be done. For example, if it can be challenged if there was:

  • Error in Test Administration
  • Faulty Equipment
  • Chain of Custody Issue: For example, if the samples were swapped or if officials lost track of the sample for any period of time. There could be an issue in court in substantiating evidence if chain of custody cannot be established. Oftentimes, many individuals need to testify to establish chain of custody and getting then into court can be difficult, resulting in a good result for the defendant.

Blood tests can be done at medical facilities, at the police station, or in special police vehicles at DUI checkpoints.

It is worthwhile to challenge urine and blood tests. A good example is a case coming out of Lancaster, Fairfield County, Ohio. The 21-year-old defendant crashed his motorcycle into a parked car. His blood test result was 0.16. A motion to suppress the results of the blood test were filed. The phlebotomist failed to show up and testify (twice) resulting in a favorable plea agreement and no conviction for OVI. The shows the benefit of challenging a blood or urine test because of all the people who have to show up and testify about the chain of custody and the myriad Ohio Department of Health regulations for handling samples.

Breathalyzer Test

The blood alcohol test most people think about is the breathalyzer test. The breathalyzer test is usually administered after someone is pulled over on the road and is suspected of a DUI.

Ohio Breathalyzer TextIf challenging the result, typically the person who administered the test is questioned about the circumstances of the test including whether or not they followed the correct procedure in administering it. Witnesses may be asked for statements and expert witnesses can be called upon to illuminate what the accepted practices are for keeping the equipment in good working order, how to give the test, and what circumstances raise red flags. It could also be helpful if you have witnesses who can testify that the amount you drank does not correspond to the results.

The results of a breathalyzer test are not always reliable, and there are a number of reasons for this:

  • Inadequate Maintenance: Breathalyzer equipment needs to be maintained like any other kind of equipment. Calibration often comes up as a problem. If the breathalyzer is not properly calibrated at regular intervals per the manufacturer, the results it gives can be inaccurate. Records need to be kept on calibration.
  • Faulty Equipment: It is always possible that a machine malfunctions. If a breathalyzer gives readings in error or otherwise malfunctions, then the results are not reliable.
  • Improper Administration or Use: The breathalyzer test needs to be administered by someone who has been properly trained and certified to do so. But even when someone who should know how to administer it has done the test, it can still be done erroneously.
  • Foreign Substances: Various kinds of foreign substances can potentially have an impact on a blood alcohol test. Mouthwash could be a problem because a breath test could read the alcohol contained in the mouthwash itself. Other ingested substances can also affect readings. Even blood could be considered a foreign substance that could impact the reading.

If you have been charged with a DUI and would like to find out if your blood alcohol test could be kept out of court, contact our Columbus criminal defense lawyers today for a free, confidential consultation at (614) 263-5297 or fill out our online form.

Categories: OVI - DUI

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