It was a belated but due step for opposition leader Kim Han-gil to issue a warning Tuesday to a party lawmaker who downplayed the Defense Ministry’s probe into the three crashed drones recently found in inter-Korean border areas as “comedy.”

Rep. Jung Cheong-rae of the New Politics Alliance for Democracy claimed last Friday the unmanned aerial vehicles might not have come from North Korea, but later changed his words after his reasoning was proven wrong. In the public eye, his flip-flopping seemed closer to comedy.

Kim’s warning showed that the largest opposition party, which was formed last month through the merger of the liberal Democratic Party and a group of followers of entrepreneur-turned-politician Ahn Cheol-soo, was sincere in gaining voter confidence in its stance on national security.

The measure will not only help boost the NPAD’s position in the run-up to the June local polls but also prevent the groundless conspiracy theory over the drones from fuelling internal disputes. The lawmaker’s claim publicized the view held by some sympathizers with North Korea that South Korea’s intelligence authorities might have orchestrated the incidents to divert attention from their recent predicament.

President Park Geun-hye apologized Tuesday for the state spy agency’s alleged forgery of evidence used in charging a North Korean defector with espionage. But she stopped short of dismissing Nam Jae-joon, director of the National Intelligence Service, who made a separate apology, pledging thorough in-house reforms.

It would have better suited public sentiment for the NIS chief to step down to take responsibility for the scandal that inflicted a deep scar on his agency’s reputation.

Pyongyang denounced Seoul on Wednesday for refusing its demand for a joint investigation into the crashed drones. North Korea’s absurd behaviors like this will be stopped only when the intelligence agency carries out its duties in a more professional, thorough and lawful way and the liberal opposition continues to keep a rational stance.