Kim Doo-woo, senior presidential secretary for public relations, resigned from his post on receiving a summons from the prosecutors’ office last weekend ― four months after his name was first mentioned in connection with an insolvent savings bank’ illegal lobbying. An arrested lobbyist for the savings bank reportedly told the prosecutors that he gave tens of millions won to Kim.

In a statement, Kim denied his culpability. He said he was resigning because he felt it inappropriate for him to be questioned by prosecutors while serving the president. At the moment, there is no knowing whether he is innocent or if he is claiming innocence until he is proven guilty, as criminal suspects tend to do. It is the prosecutors’ job to establish his guilt.

President Lee Myung-bak reportedly showed no notable emotion in signing on Kim’s resignation. But it must have been shocking for him to learn that one of his most trusted aides was involved in the corruption scandal. Kim had worked for the president since he joined the presidential staff when the Lee administration was launched in 2008.

When Kim was first mentioned in May as one of those who had close connections with Park Tae-gyu, a lobbyist for the Busan Savings Bank, President Lee appeared to have unwavering confidence in his aide.

Lee promised stern action against anyone involved in the corruption scandal one day before a commissioner of the Board of Audit and Inspection was arrested in connection with the case on May 30. He took up the issue again on Aug. 1, this time at a conference of senior presidential secretaries. With Kim attending the conference, Lee criticized the Supreme Prosecutors’ Office for failing to put the lobbyist, who had been hiding in a foreign country, into custody. Lobbyist Park was arrested when he came back to Korea on Aug. 28.

One of the questions regarding the case is: Is Lee following in the footsteps of his predecessors, from Chun Doo-hwan to Roh Moo-hyun, who were invariably hastened into lame-duck status in the fourth year of their presidency by corruption scandals involving family members or close aides?

Another question to ask is who is to be summoned next time. Kim would not be alone to be questioned by the prosecutors, given that the lobbyist spent as much as 1.5 billion won on behalf of the savings bank.