Challenging Chemical Evidence in a Georgia DUI Case

You may think the evidence against you is ironclad, but you’ll never know until you speak to a Georgia DUI lawyer with years of experience fighting these cases. In this article, the Smyrna, GA, DUI attorneys at Andrew L. Schwartz, P.C., will discuss how evidence can be challenged in a DUI case.

Challenging breathalyzer test results 

Breathalyzers are nice machines, but they’re not perfect. They test an individual’s BAC by sampling their breath. In other words, breath-alcohol is translated into blood-alcohol to determine if the individual’s BAC is over the legal limit. Problems with the breathalyzer include:

• Calibration and maintenance issues – A criminal defense attorney can subpoena the individual breathalyzer used to determine your BAC. We will look at maintenance records and the breathalyzer itself to determine if there are any calibration problems that would cause a false positive.

• Officer training issues – A criminal defense lawyer can raise a challenge if the officer administering the test wasn’t properly trained or failed to follow protocol.

• External factors and medical conditions – Some medical conditions can give false positives on a breathalyzer test or inflate your BAC. Your criminal defense lawyer can determine whether a medical condition or some other external factor has inflated your BAC. Medications, mouthwash, or medical conditions may be the likely culprits.

• Implied consent violations – Your BAC evidence can be excluded if the implied consent warning was not properly read.

Challenging blood test results 

The most accurate way to test an individual’s BAC is directly through a blood draw. The blood sample is heated up to evaporate the alcohol and used to measure the individual’s BAC. While considered the most accurate means of testing for a DUI, the process must be done exactly right in order to be considered usable in court.

• Improper procedures – Problems with the blood draw procedure itself, such as expired kits, contaminated samples, or use of non-standard equipment, can be leveraged to invalidate the results.

• Chain of custody – Errors in the chain of custody (the documentation of who handled the sample) can sometimes compromise the integrity of the results and thereby be excluded from the record.

• Storage and handling – The blood sample must be refrigerated to stop the blood from fermenting. In addition, the blood must be tested within a specific timeframe. Failure to follow these protocols exactly can cause the sample itself to be excluded from the record.

• Equipment and technician qualifications – Calibration and maintenance records of the testing equipment can be examined by your DUI attorney, as well as the qualifications of the individual who handled the blood sample.

• Denial of independent test – As a defendant, you have the right to request that an independent test be performed on your blood sample. If you are denied the right to an independent test, the prosecution’s test results could be thrown out.

Talk to a Cobb County DUI Lawyer Today 

The Cobb County DUI attorneys at Andrew L. Schwartz, P.C., represent the interests of those who have been charged with DUI in the county. Call our office today to schedule an appointment, and we can begin discussing your next steps right away.