Park Jie-won, former head of the National Intelligence Service, on Friday denied criticism that the intelligence agency was lax on counterespionage investigations under the previous Moon Jae-in administration.

People Power Party Rep. Sung Il-jong claimed in Friday’s meeting of the ruling party leadership that the Moon administration “let spy activities slide” and “tried to debilitate the NIS by stripping the intelligence agency of the authority to investigate North Korean spies and infiltrations.”

The remarks came after the NIS and police searched offices of labor unions in an investigation into their suspected links to spy activities earlier this week. The intelligence agency said the searches were conducted after “years of investigations” of the labor unions’ suspected ties with North Korea.

Park said in a phone call with The Korea Herald that the recent development in spy investigations was likely a “continuation” of investigations that were being conducted during the past administration.

“We did the investigations then, so they’re now caught,” he said.

He also voiced caution over the intelligence agency’s crackdown on North Korean spying, saying, “It’s a problem if we fail to catch spies. But it’s even a bigger problem if we falsely accuse someone of being a spy.”

He argued that it was part of “intelligence reform” to have police take on North Korea spy investigations, which had fallen within the jurisdiction of the NIS.

In December 2020, while Park was the director of the NIS, the law was revised to take away the intelligence agency’s authority to investigate espionage and meddling, handing it over to police. The revised law is set to come into effect in January next year.

On concerns that police are not well equipped to carry out the kind of undercover investigations undertaken by the intelligence agency, Park said he believes the police are “capable.”

“It’s true that there are such concerns. But this is about reform,” he said.

He said that during his time at the NIS, the spy agency and police formed a task force for joint espionage investigations, adding, “Police are capable and I already see it as the police’s authority.”

Rep. Tae Yong-ho, a former North Korean diplomat who defected to Seoul in 2016, said during Thursday’s press conference that revoking the NIS’ authority to investigate North Korean spy activities would “pose grave threats to South Korea’s national security.”

“Under the law pushed by the Democratic Party of Korea, the NIS can no longer carry out its domestic intelligence operations,” he said. “This needs to be undone.”

The Democratic Party of Korea's policy committee head Rep. Kim Sung-whan told Thursday’s meeting of party leadership that the raids of labor unions were a “return to the era when innocent South Koreans were falsely branded North Korea spies.”

“I worry that the NIS might be using this case as a tool for keeping its authority to investigate espionage.”