The Constitutional Court ruled on Thursday that a law calling for aggravated punishment against repeat drunk drivers is unconstitutional.

The country's revised Road Traffic Act, also known as the Yoon Chang-ho Act after a victim in a high-profile DUI case, was enforced in December 2018.

Seven out of nine judges on the bench ruled against a clause that subjects those caught drunk driving two or more times to harsher penalties, saying it violates the legal principles of being definitive and not excessive in passing sentences.

A majority of judges took issue with the clause lacking a specific interval between offenses, saying not all repeat drunk drivers should be considered a serious threat to the general public.

While the clause was further revised in June 2020, the current traffic law states that those caught offending two or more times must be imprisoned for two to five years or fined ten to 20 million won.