In South Carolina, DUI cases often hinge on evidence from a breath testing machine known as the DATAMASTER DMT. This device is integral to the legal process, but understanding its role and functionality can provide clarity for individuals navigating DUI charges.
DUI and Breath Testing in South Carolina
Under South Carolina law, DUI is defined as driving while "materially and appreciably impaired." Unlike other states, South Carolina does not tie DUI convictions exclusively to a specific blood alcohol concentration (BAC) level. While a BAC of 0.08% or higher may serve as evidence of impairment, it does not guarantee a conviction. Similarly, individuals with lower BAC levels can still face DUI charges if there is evidence of impairment. Consequently, breath test results are just one piece of the puzzle.
Importantly, a breath test is only offered after you have been formally charged with DUI. Once charged, you have the right to either submit to the test or refuse it. Statistically, about 40% of individuals arrested for DUI in South Carolina choose to refuse the breath test, a decision that carries its own legal consequences, such as license suspension.
How the DATAMASTER DMT Works
The DATAMASTER DMT is a sophisticated instrument used to measure the concentration of alcohol in a person’s breath. Here’s a simplified breakdown of how it operates:
Collection of Breath Sample: The process begins with the individual blowing air into the device via a mouthpiece. The machine requires a deep lung air sample, as this air closely correlates with the alcohol concentration in the blood.
Infrared Spectroscopy: Inside the DATAMASTER DMT, the breath sample is exposed to a beam of infrared light. Ethanol molecules in the breath absorb specific wavelengths of this light. By measuring the amount of light absorbed, the machine calculates the concentration of alcohol in the sample.
Conversion to BAC: The measured breath alcohol level is then converted into an approximate BAC using a mathematical formula. This conversion assumes a standard ratio between alcohol in the breath and alcohol in the blood, typically 1:2100.
Automated Safeguards: The DATAMASTER DMT performs several self-checks during the testing process:
- Calibration Checks: Ensures the machine is accurately measuring alcohol levels.
- Blank Tests: Confirms no residual alcohol is present in the machine before testing.
- Control Tests: Uses a pre-measured alcohol sample to verify the device is functioning properly.
Printout of Results: Once the test is complete, the DATAMASTER DMT generates a report indicating the individual’s breath alcohol concentration. This report is used as evidence in court but is not the sole determinant of guilt.
Potential Issues with the DATAMASTER DMT
While the DATAMASTER DMT is a precise instrument, it is not infallible. Several factors can impact the accuracy of its readings:
- Improper Maintenance or Calibration: Regular maintenance and calibration are essential for accuracy. Any lapse in these procedures can lead to erroneous results.
- Environmental Factors: Substances like acetone, present in diabetics or individuals on certain diets, can interfere with readings. Similarly, residual alcohol in the mouth (e.g., from recent mouthwash) can skew results.
- Human Error: Errors in administering the test, such as failing to observe the individual for the required 20-minute observation period before testing, can compromise its validity.
Refusing the Breath Test: Pros and Cons
As noted earlier, many individuals in South Carolina opt to refuse the breath test. While refusal can limit evidence against you, it also triggers automatic penalties, including:
- An immediate license suspension (up to six months for a first offense).
- The requirement to complete the Alcohol and Drug Safety Action Program (ADSAP).
- Installation of an ignition interlock device for certain offenders.
Understanding your rights and the implications of refusal is crucial when faced with this decision.
Conclusion
The DATAMASTER DMT plays a significant role in South Carolina DUI cases, but its results are not definitive proof of guilt. Understanding how the device works—and its potential weaknesses—can provide a strong foundation for your defense. If you or someone you know is facing a DUI charge, consulting with an experienced criminal defense attorney is the best way to navigate the complexities of the legal system and build a robust defense.
If you or a loved one has been charged with DUI in South Carolina, it’s crucial to act quickly to protect your rights and your future. At the Law Office of James R. Snell, Jr., LLC, we have the expertise and experience to help you fight DUI charges—whether breath test results are involved or not. James Snell, the author of South Carolina DUI Defense: The Law and Practice, is not only an experienced DUI defense attorney but also a certified NHTSA DWI Detection and Field Sobriety Testing instructor. Having represented hundreds of individuals in Lexington, Columbia, and throughout South Carolina, he knows how to navigate the complexities of DUI cases to protect your license, freedom, and reputation.
DUI cases are time-sensitive, and taking the right steps early can make all the difference. Contact our office today for a free consultation and let us start building your defense. Call (803) 359-3301, same day appointments are typically available.