Case Overview:
The defendant, referred to as A, was involved in a fatal hit-and-run in Gwangju while driving a Maserati. He struck a motorcycle at high speed, fled the scene, and was later charged with DUI, aiding escape, and fatal hit-and-run (도주치사).

Incident Details:

Date: September 24, 2024, around 3:10 a.m.

Location: Gwangju Seo-gu (western district).

Speed: 128 km/h in a 50 km/h zone.

Victims: Two people on the motorcycle were seriously injured; one later died.

After the crash, A fled without offering aid and asked a friend to help him hide and obtain a burner phone.


Lower Court Decisions:

1st Instance (Trial Court): Found guilty on all counts → sentenced to 10 years in prison.

Appeal Court:

Acquitted A of DUI and aiding escape.

Upheld guilt for hit-and-run causing death → sentence reduced to 7 years and 6 months.



Key Legal Issue — The Widmark Formula:

The prosecution estimated A’s blood alcohol level using CCTV footage of his drinking before the accident.

The appellate court ruled this was insufficient proof, as the exact quantity of alcohol consumed couldn’t be determined from the footage.

It emphasized that the Widmark formula (used to calculate blood alcohol content retroactively) requires strict proof of all underlying facts.

Even if used, the calculation must apply the most favorable assumptions to the defendant (lowest absorption rate, immediate alcohol breakdown, etc.).

Under those conditions, the blood alcohol concentration could not be proven to exceed 0.03%, the legal threshold for DUI.


Aiding Escape Charge:

The court found that A’s actions were ordinary evasive behavior after a crime and did not constitute an active attempt to deceive investigators or abuse of defense rights.


Supreme Court Decision (Final Judgment):

Date: October 16, 2025

Court: Supreme Court Criminal Division 2 (Justice Eom Sang-pil)

Outcome: Upheld the appeal court ruling →

Guilty of fatal hit-and-run.

Not guilty of DUI and aiding escape.


The Court stated that the lower court’s reasoning did not violate logic, experience, or legal principles.


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Key Takeaways

The Widmark formula cannot be freely used unless each assumption (drinking amount, timing, metabolism rate, etc.) is strictly proven.

CCTV evidence alone is insufficient to determine alcohol intake for DUI charges.

Courts must apply the most lenient scientific assumptions in favor of the defendant when BAC cannot be measured directly.

The decision reinforces due process and evidentiary rigor in DUI prosecutions based on retroactive estimation.

Article: https://www.lawtimes.co.kr/Case-curation/212842