The Supreme Court on Thursday finalized an 18-month prison term for an aide to former President Park Geun-hye for leaking confidential presidential documents to Park’s friend at the center of a massive corruption scandal.

It was the first Supreme Court verdict on a case implicating Park as an accomplice in the influence-peddling scandal that led to her impeachment and removal from office last year.

Jeong Ho-seong was indicted last November for providing 47 classified documents, under Park’s instructions, to Choi Soon-sil who is accused of exploiting her ties with the ex-president to meddle in state affairs and extort money from conglomerates.

The documents provided to Choi included recommendations for Park’s special envoys to China, drafts for her presidential address in Dresden, opening remarks at a Cabinet meeting and itineraries for her overseas trips. Jeong was also indicted for non-attendance of a hearing for a related parliamentary inquiry.

The top court upheld the lower courts’ rulings that found Jeong guilty of leaking 14 confidential documents.

The lower courts said the other 33 documents were inadmissible as evidence as they were unlawfully seized by investigators under a search warrant unrelated to the case.

Park, indicted as Jeong’s accomplice in the case, was also found guilty for the leaking of only the 14 documents in her first trial early this month.

Park did not appeal, but prosecutors appealed to a higher court, insisting she is guilty of leaking the other 33 documents as well.

Jeong was one of the three longest-serving aides to Park, along with Lee Jae-man and An Bong-geun. They were called the “doorknob trio” by the media as they were said to be holding the door to Park’s office, or having exclusive access to the reclusive former president.

The Seoul Central District Court sentenced former President Park to 24 years in prison and a fine of 18 billion won ($16.7 million) early this month, convicting her of 16 charges, including abuse of power, coercion, bribery and the leaking of government secrets.

The Seoul court sentenced Choi to 20 years in jail and a fine of 18 billion won in February on the conviction of bribery, abuse of power and coercion.

By Kim So-hyun (sophie@heraldcorp.com)