Case Analysis / Legal Updates

Drunk Driving Appeal | A Case Reversed to Acquittal on Appeal After a Fine Was Imposed at the First Instance

Through a drunk driving appeal, a driver who had been sentenced to a fine at the first instance obtained an acquittal on appeal. The appellate court explained that the rising phase of the blood alcohol concentration had to be taken into account.

1. Drunk Driving Appeal, the Detailed Circumstances

A, who filed the drunk driving appeal, was at a blood alcohol concentration of 0.032% charged by summary indictment* for having driven approximately 6 km.

Under the current Road Traffic Act, the enforcement threshold for drunk driving is set at a blood alcohol concentration of 0.03%, and A's reading slightly exceeded this figure.

Contesting this, A requested a formal trial and argued, "Because I was in the rising phase of the blood alcohol concentration at the time of the breath test, the level did not exceed 0.03% at the time of driving."

The court of first instance, however, determined that A's blood alcohol concentration at the time of driving was 0.03% or higher and found that the drunk driving charge was established. The court cited as grounds that A had rinsed his mouth with water before the breath test, had not raised any objection to the breath test result, and had been tested approximately five minutes after finishing driving.

A then objected to the first instance court's determination and filed the drunk driving appeal.


* Summary indictment: a request by the prosecution that the court issue a summary order where it determines that the crime committed by the suspect warrants a fine rather than imprisonment with or without labor

Drunk Driving Appeal, the Applicable Statutes

🔗Punishment for drunk driving is provided for in the Road Traffic Act.

▣ Article 44 of the Road Traffic Act (Prohibition of Drunk Driving)

① No person shall drive a motor vehicle while in a state of intoxication.

② The state of intoxication referred to in paragraph 1 means a state in which the driver has a blood alcohol concentration of 0.03% or higher.

Where the moment of a driver's breath test falls within the rising phase of the blood alcohol concentration, the actual reading may not be accurate.

In general, after a person drinks, the blood alcohol concentration holds at a certain level, rises to its peak roughly 30 to 90 minutes after drinking, and then gradually declines. For this reason, where there is a time gap between the actual driving and the moment of detection, the "Widmark formula," a method of estimating the blood alcohol concentration, is used.

The Widmark formula is a technique that, taking into account that the blood alcohol concentration rises until about 90 minutes after drinking and then begins to fall, back-calculates what the blood alcohol concentration actually was at the time of the drunk driving by considering the type and amount of alcohol consumed, the time of drinking, body weight, the in-body absorption rate, and other relevant factors. Using this formula, a person may file a drunk driving appeal.

2. Drunk Driving Appeal, the Appellate Court's Determination

The appellate court that heard the drunk driving appeal, unlike the first instance court, acquitted A.

Citing Supreme Court precedent, the appellate court stated that "in the case of a breath-based alcohol test, the accuracy and reliability of the result may be compromised depending on the condition of the measuring device, the method of measurement, and the degree of cooperation," and determined that, considering that the reading exceeded the punishment threshold by only 0.002%, it was difficult to conclude that the concentration at the time of measurement was 0.03% or higher.

In addition, the court found that the difference between A's last drinking time and the time of the breath test was only 15 minutes, so that the blood alcohol concentration was highly likely to have been rising during this period.

Beyond this, the fact that the two acquaintances who had shared one bottle of soju with A were not caught in the drunk driving crackdown also served as a ground for the acquittal.

3. Drunk Driving Appeal, Daeryun's Strategy

This was a District Court judgment that, taking into account the rising phase of the alcohol concentration through the drunk driving appeal, determined that at the time of the breath test the level would not have exceeded the 0.03% enforcement threshold and accordingly acquitted the defendant.

Those who are currently on trial on a drunk driving charge or are preparing an appeal may refer to this precedent and actively rely on the Widmark formula to assert that there was no offense.

Daeryun Law Firm LLP has extensive experience in cases involving drunk driving and traffic accidents, including the 🔗case in which an acquittal was obtained by asserting the rising phase of the blood alcohol concentration, and it thoroughly analyzes the applicable statutes to protect clients' rights and interests.

If you feel that the punishment imposed for drunk driving is unjust and wish to pursue a drunk driving appeal, you are welcome to request assistance from Daeryun at any time. 🔗An attorney experienced in drunk driving and traffic accident matters will actively assist you.

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