Acquittal in a Korean Lane-Change Graze Case Where a Two-Week Injury Was Not Proven

Case Overview

A driver changing lanes on a multi-lane urban road at dusk grazed the side of another vehicle on the way to an exit. The contact was so light that the driver did not feel it and did not realize an accident had occurred. The next day, the other driver submitted a medical certificate calling for two weeks of treatment, and the driver was indicted for causing injury under Korea's Traffic Accident Special Treatment Act. The decisive question was not whether the lane change had been negligent, but whether the contact had caused an injury that Korean criminal law recognizes. Using three synchronized dashcam recordings, a factual inquiry to the treating clinic, and cross-examination of the other driver, the defense showed that a two-week injury had not been proven beyond a reasonable doubt. The court acquitted.

Background

The client was driving in the evening on a multi-lane arterial road in a Korean city and was preparing to take an exit. The client activated the turn signal and moved into the outer lane. The lane markings at that point permitted the change. As the client's vehicle entered the lane, the front of the car lightly touched the side of a vehicle already traveling there. The contact was so weak that the client felt no impact and did not know an accident had happened, so the client continued driving.

The other driver later reported the incident, and a hit-and-run allegation — failing to stop and take the required measures after a traffic accident — was opened. At the police stage, that allegation was closed without referral to the prosecution. The next day, however, the other driver produced a medical certificate stating that two weeks of treatment were needed. On that basis, the client was indicted for violating the Traffic Accident Special Treatment Act by causing injury through a negligent lane change.

Criminal Allegation

The charge was causing injury by negligent driving under the Traffic Accident Special Treatment Act, with the lane change as the underlying negligence. The prosecution's case rested on two elements: that the client had changed lanes carelessly, and that the other driver had suffered an injury requiring two weeks of treatment. In many traffic cases, a short-term medical certificate is enough to support a charge at the filing stage.

The defense did not dispute that the vehicles touched. It disputed whether the contact produced an injury that meets the legal definition, and whether the evidence proved that beyond a reasonable doubt.

Key Legal Issues

Korean criminal law does not treat every ache or bruise as an injury. The concept generally requires an impairment of the body's physical integrity or a restriction of physiological or daily function. An extremely minor condition that would resolve naturally without treatment ordinarily falls outside it. A medical certificate is evidence, not a conclusive finding. Where a diagnosis rests mainly on the patient's subjective complaints of pain and is not supported by objective testing, a court must assess its reliability rather than accept it automatically.

Causation was the second issue. Even if the other driver experienced some discomfort, the defense had to examine whether it came from this contact or from a condition that predated the accident. Korean courts decide these questions on the evidence presented, so recording quality, medical records, and the consistency of witness statements can change the result.

A third issue was the weight of the earlier hit-and-run outcome. The police had already declined to refer that allegation. The reason for that decision — that the contact was minimal — was relevant context for the injury charge, though the two allegations were legally distinct.

Defense Strategy

The defense treated the case as a proof problem and built the record around objective evidence.

Reconstructing the moment from three dashcams. The team synchronized footage from three sources second by second: the other vehicle's dashcam, the client's dashcam, and the dashcam of a third vehicle following behind. The other vehicle's recording showed the client's car moving into the lane at a point where lane changes were permitted, at a comfortable distance, with the turn signal on. The audio captured only music, with no impact sound. The third vehicle's footage showed no visible collision at the same moment.

Using the hit-and-run outcome. The defense pointed out that the client had left without inspecting any damage and had taken a polygraph examination in which all responses registered as truthful. The police had closed the hit-and-run allegation without referral. The defense argued that this independent outcome supported the conclusion that the contact had been extremely light.

Comparing a prior judgment. The defense submitted a court decision in which the National Forensic Service had found that the impact in question could not have caused injury, leading to an acquittal. In that case the vehicle had cut in at about 30 km/h. Here, the client had been moving at less than 10 km/h in congested traffic, had no hit-and-run referral, and had caused only minor surface damage. Placing the two cases side by side showed that this contact was the lighter of the two.

Testing the diagnosis. The defense requested a factual inquiry to the medical institution that issued the certificate. The clinic confirmed that it had diagnosed and treated the other driver based on consultation and the symptoms the patient reported, without X-ray or CT imaging. The inquiry also showed that the other driver had been receiving treatment at the same clinic for the same part of the body before the accident.

Challenging the testimony. During the investigation, the other driver said the client's car had hit the side and that there had been a thud. In court, the account changed to the car having been pushed. The defense highlighted the shift, argued that the injury account had been exaggerated, and declined to consent to the use of the earlier statements as evidence where their reliability was in doubt.

Outcome

The court acquitted the client. It held that the prosecution had not proved beyond a reasonable doubt that the contact caused a two-week injury recognized under criminal law.

The judgment rested on four points. First, both vehicles had been moving slowly, and at the moment of contact the other car was only slightly pushed, with no sound or shaking. Second, most of the repair estimate — several hundred thousand won — was for exterior work such as panel beating and painting, with no indication of structural damage to the body. Third, the physician appeared to have inferred the symptoms from the patient's own account without imaging tests. Fourth, because the other driver had been treated for the same area before the accident, the effect of pre-existing symptoms could not be excluded.

The court accepted that the other driver may have felt pain. It concluded, however, that this did not establish an impairment of physical integrity or a loss of ordinary function. The client was acquitted, and no conviction followed.

What This Case Shows

This case illustrates that, in Korean traffic-injury prosecutions, a two-week medical certificate does not end the inquiry. Whether the contact caused a legally recognized injury is a separate element that the prosecution must prove with reliable evidence.

It also shows how much can turn on the record. Footage from other vehicles, not only the client's own dashcam, can establish the force of a collision and whether the driver could have perceived it. A factual inquiry to the treating institution can reveal whether a diagnosis rested on objective testing or only on reported symptoms. A history of treatment for the same area before the accident is a factor courts will weigh. And where a witness's account changes between the investigation and the courtroom, the earlier and later versions should be compared carefully.

Every case depends on its own facts. The degree of contact, the medical evidence, and the credibility of the witnesses vary, so similar-sounding cases can produce different outcomes. A driver facing a traffic-injury charge should preserve evidence early and have the medical basis of the accusation examined closely.