An Experienced Criminal Defense Attorney Can Challenge Your Breath And Field Sobriety Tests
Last updated on March 16, 2026
Just because you fail a breathalyzer test does not necessarily mean a conviction for a DUI/DWI is imminent. Consulting with an experienced criminal defense lawyer who regularly handles DUI cases is always worthwhile. As former prosecutors, the criminal defense attorneys of Young & Young, Attorneys at Law, understand how Charleston prosecutors approach these cases and, more importantly, know how to defend against them.
Can You Refuse A Breathalyzer Test In South Carolina?
If you refuse to take a breathalyzer test in South Carolina, your license will automatically be suspended for at least six months without exception. Most states, including South Carolina, have an implied consent law for chemical testing to determine the presence of drugs or alcohol in your system. This means that by holding a South Carolina driver’s license, you have already consented to chemical testing, including breathalyzer tests, as a condition of licensure.
Can You Refuse To Take Field Sobriety Tests In South Carolina?
While you are required, by law, to submit to chemical testing like a breathalyzer test in South Carolina, field sobriety tests are voluntary. You have the constitutional right to refuse to take any field sobriety tests that law enforcement officers ask you to complete.
Analyzing The Facts Of A DUI Arrest
After years of prosecuting cases for South Carolina, our attorneys have seen enough fact patterns and cases to quickly analyze whether the state has a good case. We will examine the breath and standardized field sobriety tests you were given to determine if the results are admissible. If they are not, we will argue for suppressing the evidence. This may lead to a reduction or dismissal of the charges.
When Are The Results Of A Breathalyzer Test Inadmissible?
In South Carolina, any arrest for a DUI, chemical tests and field sobriety tests performed during a traffic stop are required to be videotaped. If a video was not taken or the subsequent recording is of poor quality, our DUI attorneys can argue that your rights were violated.
We will view any arrest tapes and relevant evidence to determine if law enforcement officers followed the proper procedures during every stage of the arrest, whether chemical testing or field sobriety tests. If the officer failed to administer the tests correctly, under the right conditions or was unable to observe your tests accurately,
If you are arrested, there will be additional steps and a breath test at the police station. We will also examine any video from your arrest and booking and the results of any other tests to ensure proper protocols were followed. We may also investigate the breath test machine’s calibration or maintenance history and any factors that may have affected the results.
The Science Of A Flawed Result
Breath tests and field sobriety tests are often presented as scientific proof of intoxication. In reality, both rely on strict procedures and assumptions that can produce unreliable results when mistakes occur.
South Carolina officers commonly use the DataMaster DMT breath testing machine. While it estimates blood alcohol content, the reliability of its results depends on proper operation and maintenance. Several factors can affect the accuracy of a breath test, including:
- Improper device calibration or maintenance
- Residual mouth alcohol from recent drinks, mouthwash or medication
- Failure to follow the required observation period before testing
- Radio frequency interference or environmental conditions
- Operator errors during the testing process
Attorneys frequently examine maintenance records, officer training and testing procedures to determine whether the breath test result can be challenged.
Standardized field sobriety tests also contain potential weaknesses. The National Highway Traffic Safety Administration created these tests, but their reliability depends on proper administration and suitable conditions. Problems can arise when officers conduct tests on uneven pavement, in poor lighting or without clear instructions. Physical injuries, age, fatigue or anxiety during a roadside stop may also affect performance.
DUI Breath And Field Sobriety Test FAQs
The following are answers to common questions Charleston drivers ask about breath tests and field sobriety tests during DUI investigations.
Can I challenge a breathalyzer result if I have a medical condition?
Yes. Certain medical conditions may influence breath test results. Conditions such as acid reflux, diabetes or respiratory issues can produce substances that interfere with breath testing equipment. When medical factors are involved, a defense attorney may examine testing procedures, machine records and medical documentation to determine whether the result is reliable.
Are South Carolina field sobriety tests always accurate?
No. Field sobriety tests depend heavily on officer observation and interpretation. Uneven surfaces, poor lighting, nervousness or physical limitations can all affect performance. For this reason, attorneys often review the conditions of the test and any available video evidence when evaluating the results.
What happens if the officer did not record my DUI arrest?
South Carolina law generally requires DUI stops and testing procedures to be recorded. If the recording is missing or incomplete, it may raise questions about whether proper procedures were followed and whether certain evidence can be used in court.
Careful review of breath testing procedures and field sobriety testing can reveal important issues in a DUI case.
Schedule A Free Consultation With A Charleston DUI Lawyer
Our firm offers free consultation appointments to discuss your case. Call us at 843-619-7755 to schedule your free consultation. You may also contact us online if you prefer.
