When a police officer pulls you over, they will ask you many questions about your behavior. If they think you may have had too much to drink, they will ask you to perform field sobriety tests or maybe a chemical breath test.
The results of your performance on those tests could mean that the officer arrest you. Sometimes, there was no sign of impairment before the traffic stop. The officer noticed that your speed exceeded the posted limit or maybe that your brake light was out, so they pulled you over. It was only after talking to you that they began to suspect impairment.
If you fail the breath test, can they charge you with drunk driving even though your control of the vehicle was fine?
Drunk driving can be a technical offense
The state can charge you with impaired driving because of how you behave at the wheel. The more erratic and unpredictable your driving is, the more likely an officer would have probable cause to arrest you for drunk driving.
However, chemical impairment is not just about your performance at the wheel. It is also about the presence of mind-altering substances in your bloodstream. South Carolina has a per se limit for your blood alcohol concentration (BAC) that limit is 0.08% for the typical adult. For those under the age of 21, the limit is just 0.02%.
If a breath test show results higher than that limit, the driver has committed a technical infraction based solely on the level of alcohol in their body.
Challenging the breath test can help those accused of a per se offense
If the only evidence that the state has to back their claims of drunk driving is the record of a chemical breath test, then challenging the accuracy of that test could be a successful defense strategy.
Some drivers could offer medical evidence showing why their results may have been higher than normal. Others could review the maintenance record for the testing unit used during their arrest and point out failures by the police department that could cause inaccurate test results.
Knowing the rules that apply to drunk driving charges can help those who need to defend themselves.