Lim, 59, is suspected of being the key man who helped former Supreme Court Chief Justice Yang Sung-tae use trials as bargaining chips in dealings with the presidential office under the previous Park Geun-hye government. Lim worked for the NCA from 2012-2017.

Prosecutors believe Yang sought to curry favor with Park's office by having the NCA devise plans to influence politically sensitive trials to Park's advantage, so as to win her approval for establishing a separate court of appeals.

Among the trials in question are the long-pending compensation case for Korean victims of Japanese wartime forced labor and a case that involves a progressive teachers union.

Lim underwent prosecution questioning on Oct. 15. He has denied any wrongdoing.

The court is expected to reach a decision late Friday or early Saturday. (Yonhap)