Blood alcohol test results in a Georgia DUI case can be challenged on multiple grounds, including improper blood draw procedures, chain of custody failures, lab errors, and physiological factors that affect BAC readings. A positive BAC result is not the end of your case. Kim Keheley Frye holds the ACS-CHAL Forensic Lawyer-Scientist designation, one of the only attorneys in this market with the credentials to challenge blood and breath test evidence at the level of the underlying science, not just by legal argument.
If you are facing a DUI charge in Georgia based on a blood alcohol test, the result feels like a locked door. But blood alcohol testing is not as airtight as it appears, and an experienced DUI defense attorney knows exactly where to look for problems.
Kim Keheley Frye and the team at Frye Law Group have challenged blood and breath test results throughout Marietta and Cobb County. Below we break down how these tests work, where they fail, and how a challenge can change the outcome of your case.
How Blood Alcohol Testing Works in Georgia
In Georgia, there are a number of tests officers can use to check blood alcohol content (BAC) levels. Though breath tests are the most well-known and easiest to administer, they are not the only option.
Blood alcohol tests, performed in a lab by drawing and analyzing a sample of your blood, are often considered more accurate, and they are increasingly common in DUI cases, particularly those involving accidents, serious injury, or drug impairment alongside alcohol.
Under Georgia’s implied consent law, drivers who are lawfully arrested for DUI are required to submit to chemical testing. A blood test result above the legal limit of 0.08% for most drivers, 0.04% for commercial drivers, and 0.02% for drivers under 21 can be used as evidence against you in both the criminal case and the administrative license suspension proceeding.
Where Blood Alcohol Tests Can Go Wrong
Even blood alcohol tests have potential weak points. Understanding them is the foundation of any effective challenge.
Physiological Factors That Affect Results
Your health and diet can affect BAC readings in ways that have nothing to do with how much you drank. People with conditions that produce elevated ketones, including diabetes, low-carb diets, or fasting, can register falsely elevated BAC results on certain tests. High blood sugar can also skew readings. These are not technicalities; they are documented scientific phenomena that a qualified attorney can raise with evidence.
Chain of Custody and Sample Integrity
A blood sample taken at the time of your arrest must be properly labeled, stored, transported, and logged at every step before it reaches the lab. Any break in that chain of custody raises legitimate questions about whether the sample tested was actually yours and whether it was properly preserved. Blood samples that are not stored correctly can ferment, artificially elevating the alcohol content in the sample itself.
Lab Procedures and Human Error
Lab technicians are human. Overworked labs can mix up samples, use improperly calibrated equipment, or fail to follow the specific testing protocols required for results to be admissible. Even a small procedural deviation can provide grounds to challenge the reliability of the result. In some documented cases, samples have been left out long enough to coagulate, directly affecting the reading.
The Testing Method Itself
Blood alcohol testing in Georgia DUI cases is typically performed using headspace gas chromatography, a specific laboratory method for measuring alcohol concentration in blood. The accuracy of this method depends heavily on proper calibration, correct use of internal standards, and adherence to established protocols.
Kim Keheley Frye holds the ACS-CHAL Forensic Lawyer-Scientist designation from the American Chemical Society, which is the only credential of its kind held by an attorney in this market. This means she can challenge the science behind these tests at the level of the chemistry itself, not just by raising procedural objections.
Challenging Breath Tests in Georgia
Breath tests have their own set of vulnerabilities. Officers must calibrate breathalyzer devices correctly and follow specific protocols during administration. Anything with alcohol content (such as cough drops, mouthwash, and certain foods) can affect the reading. Even mouth alcohol from a recent belch or reflux event can produce a falsely elevated result. The device itself must be properly maintained and regularly calibrated, and records of that maintenance must be available for review.
Georgia law requires breath test operators to hold a valid permit and follow specific procedures during the test. Failure to comply with these requirements can provide grounds to suppress the breath test result entirely.
What Happens When Test Results Are Successfully Challenged
If a blood or breath test result is successfully challenged and suppressed, the prosecution loses its primary scientific evidence of impairment. In many cases, this fundamentally changes the strength of the state’s case and opens the door to a reduction, a dismissal, or a not guilty verdict at trial. In other words, a BAC result that seems ironclad on paper is not always ironclad in court.
Talk to a Marietta DUI Defense Attorney
A blood alcohol test result does not automatically mean a conviction. The science behind these tests has real vulnerabilities, and an attorney who understands that science, not just the law, can make a significant difference in the outcome of your case.
If you are facing a DUI charge in Marietta or Cobb County, call Frye Law Group today for a free case evaluation. The science is challengeable, but only if the right attorney is looking at it.
Frequently Asked Questions About Challenging Blood Alcohol Test Results
1. Can blood alcohol test results be challenged in a Georgia DUI case?
Yes. Blood and breath test results can be challenged on multiple grounds, including improper collection or storage of the blood sample, chain of custody failures, lab errors, equipment calibration issues, and physiological factors that affect BAC readings. A successful challenge can result in the test result being suppressed, which significantly weakens the prosecution’s case. Frye Law Group handles these challenges throughout Cobb County.
2. What is headspace gas chromatography, and why does it matter in a DUI case?
Headspace gas chromatography is the laboratory method most commonly used in Georgia to measure blood alcohol concentration in DUI cases. The accuracy of the result depends on proper calibration, correct use of internal standards, and strict adherence to testing protocols. Kim Keheley Frye holds the ACS-CHAL Forensic Lawyer-Scientist designation, which allows her to challenge this evidence at the level of the underlying chemistry.
3. Can medical conditions affect a blood alcohol test result in Georgia?
Yes. Conditions that produce elevated ketones, such as diabetes or a low-carb diet, can cause falsely elevated BAC readings on certain tests. High blood sugar can also affect results. These are documented scientific issues that can be raised as part of a DUI defense with appropriate medical evidence.
4. What is chain of custody, and why does it matter in a DUI blood test case?
Chain of custody refers to the documented record of how your blood sample was handled from the moment it was drawn to the moment it was tested. Any gap or irregularity in that chain raises questions about whether the sample was properly preserved and whether the result is reliable. A break in chain of custody can provide grounds to challenge the admissibility of the test result.
5. Can a breath test result be suppressed in a Georgia DUI case?
Yes. Breath test results can be suppressed if the device was not properly calibrated, if the officer failed to follow required protocols, or if mouth alcohol from a recent belch or reflux event affected the reading. Georgia law requires breath test operators to hold a valid permit and follow specific procedures. Contact Frye Law Group if you believe your breath test result may be challengeable.
6. What happens if a blood alcohol test result is suppressed in my DUI case?
If the test result is suppressed, the prosecution loses its primary scientific evidence of impairment. Depending on what other evidence exists, this can lead to a reduction of the charge, a dismissal, or a not guilty verdict at trial. Kim Keheley Frye has the scientific credentials and courtroom experience to pursue suppression effectively.
7. Does a high BAC result mean I will be convicted of DUI in Georgia?
No. A BAC result above the legal limit is powerful evidence, but it is not automatically conclusive. It can be challenged on scientific, procedural, and physiological grounds. The strength of that challenge depends on who is examining the evidence and how deeply they understand the science behind the testing. Contact Frye Law Group for a free case evaluation.