One very important aspect of DUI and DUAC cases in South Carolina, or anywhere for that matter, is what the “legal limit” of alcohol even is!!

It may seem confusing, but in SC thinking of DUI’s and DUAC’s in terms of violating the “legal limit” is wrong. But how can this be? When we watch the news or read the newspaper, the media always talks about the “legal limit.” We hear discussions about how much alcohol you can consume and stay under the legal limit. So, what does this mean?

In the entire South Carolina Code of Laws, there is not one mention of a “legal limit” for alcohol consumption in SC.

So if there is no “legal limit,” how do Breathalyzer and Blood Test Results Work in SC?

SC law breaks down the results of the Breathalyzer (if you decide to blow) or the blood test into ranges based on the BAC readings from those tests.

When SC law addresses a certain percentage, it means the percentage of ethanol found in the breath, blood or urine. For our purposes, ethanol = alcohol.

Let’s break down what the law actually says in SC…

  • A reading of .00 to .05 creates a “conclusive presumption” that the person was NOT under the influence.
  • A reading of .05 to .07 does not give rise to even an “inference” that the person was under the influence but may be considered by a jury along with other evidence.
  • A reading of .08 or more creates an “inference” that the person was under the influence – not a presumption. A presumption has been held to shift the burden of proof back to an accused in violation of his right to not have to prove his innocence.

See? There is no mention of what the legal limit is in the law!

Is the “BAC” different for under-age drivers?


Here is the law for under-age drivers:

South Carolina has a zero-tolerance policy when it comes to minors drinking and driving. If you are under the age of 21 and get caught driving with a BAC of at least .02% or more, you will face consequences. For a 1st offense violation, your license will be suspended for 3 months. For a 2nd offense violation within 5 years of your 1st offense, your license will be suspended for 6 months.

The consequences are a little different if you refuse a Breathalyzer test. If you refuse to blow, your license will be suspended for 6 months for a 1st offense, and 1 year for a 2nd offense within 5 years of your 1st offense.

This zero-tolerance under 21 policy provides for license suspensions. An officer can take you to a breath testing device if he has reasonable suspicion that you are under 21 and that you have consumed alcoholic beverages. This is really an arrest, but the law refers to it as a brief detention. If your license is suspended based on the reading or refusal, this brief detention can become an arrest if the officer elects to charge you with DUI or DUAC.

In practice, it seems that officers will book you into jail under a ticket that reflects a violation of 56-1-286 when in fact that is not a criminal offense. The law needs to be clarified or amended.

Do commercial drivers face harsher consequences for drinking alcohol and driving?


In South Carolina if you are caught drinking and driving, you will lose your CDL license for one year if:

  • you are convicted of DUI or DUAC while driving a commercial vehicle OR any other type of vehicle
  • you are caught drinking and driving while driving a commercial vehicle and your BAC is .04% or higher
  • you are caught drinking and driving and refuse to give a blood, urine, or breath test

If you happened to be transporting hazardous materials at the time you were caught drinking and driving and end up being convicted of DUI or DUAC, you will lose your CDL license for 3 years.

You can even lose your CDL license permanently if you have two DUI convictions.

Now let’s talk about what the SC law means…

What is a “conclusive presumption?”

If there is a conclusive presumption about something, it means that there is a fact that is automatically established as true.

If your blood or urine tests produce a reading of .00 to .05 you are conclusively presumed to NOT be driving under the influence of alcohol.

So what does this mean for DUI’s and DUAC’s??
If your blood or urine test produce a reading of .08 or more it can be inferred that you were under the influence. If your case went to trial, the jury or court (if the trial is judge-alone), need not accept that reading. The jury can decide what weight to give the reading as they can do as to any other evidence.

What is an “inference?”

If there is an inference about something, it means that the piece of evidence can either be believed to be true, or believed to be false. It is not automatically one or the other. The most important consideration is that the defendant need not respond with evidence to counter the inference. That would shift the burden of proof to defendant who need take no action in his defense. Every person facing a criminal charge is presumed innocent. That is the burden of proof the prosecution must bear.

What You Should Be Thinking At This Point

Because of the difference that even .01% in your urine or blood test reading can make in your case, and how important those ranges in the law explained above are, it is very beneficial to hire an experienced DUI attorney to counsel you through your DUI or DUAC case.

A DUI lawyer needs to be knowledgeable about blood testing, breath alcohol testing devices and the science that applies. He needs to have a library of resource material available on the science that applies to any alleged result of these types of testing. Using this knowledge, experience and skill, he needs to be able to challenge the accuracy and precision of results the prosecution offers as accurate evidence.

At Kulp & Elliott we do and we can.

So How Open to Challenge Are Breath Test Readings?

A complete answer to this question is too involved to be addressed here. But several considerations can be quickly mentioned.

It is important to note a fundamental consideration as to this testing. Results are reported as being a value of one percent. For example, .08 of 1%.

Expressed as a quantity, not a percentage, .08 of 1% is .0008.

Why is this important? The very minute measurement here is critical.

Let’s say a person is alleged to have had a breath alcohol reading of .08 of 1% or .0008.

Back to the statutory, conclusive presumption that a person is NOT under the influence if alcohol if the reading produced is .05 of 1% or less.

If .05 of 1% or .0005, the difference between that value and .08 of 1% or .0008, is .0003.

Correct. .0003. Thus, the difference between a conclusive presumption of no being under the influence and an inference that a person is, is a mere margin of three ten-thousands.

This is why knowledgeable analysis and investigation of a breath test reading is critical to preparation of any DUI defense where a reading is involved. No criminal defense lawyer should shy away from science. DUI defense is all about science, math and human physiology.

Hiring an experienced DUI attorney in South Carolina can make a huge difference in the outcome of your DUI case. It can affect the amount of time a convicted person spends in jail. The accuracy and reliability of your breath and blood alcohol readings should be questioned since they have such a big impact on the outcome of your case.

What test results, particularly test results produced by machines that have seriously impacts on our lives, should not be questioned for accuracy and reliability? Answer: all.

What Should You Do Next?

If you are facing DUI or DUAC charges in SC you need the help of an experienced South Carolina DUI/DUAC attorney. You probably have questions about your arrest and how a conviction could impact your life. The law in SC about the legal limit of alcohol is complex, and an experienced DUI attorney can help walk you through it.

Ready to Speak with an Attorney?

Contact Timothy Kulp to discuss your situation.

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