South Korea police seek exit ban on ex-U.S. envoy over defamation probe

South Korean police have applied to the Ministry of Justice for an exit ban on Morse Tan, a Korean American professor and former U.S. ambassador at large, as authorities investigate defamation allegations tied to false statements he made about President Lee Jae Myung, The Korea Times reported Monday.

The case, rooted in claims Tan made at a Washington D.C. press conference in June 2025 that courts have since ruled false, tests whether South Korean authorities can assert criminal jurisdiction over defamatory speech that originated on U.S. soil.

Park Jeong-bo, head of the Seoul Metropolitan Police Agency, said at a regular press briefing Monday that officers would carry out "the necessary investigation according to established procedures," according to The Korea Times.

Tan, also known by his Korean name Dan Hyun-myung, served as U.S. ambassador at large for global criminal justice under the first Trump administration. He returned to South Korea on Thursday, saying he planned to monitor the June 3 local elections for alleged irregularities.

At a Washington D.C. press conference in June 2025, Tan claimed President Lee had been confined in a juvenile detention facility following involvement in rape and murder. Courts subsequently ruled those claims false, according to The Korea Times.

Police initially closed the case. But on May 13, prosecutors ordered investigators to reopen it, arguing that a crime's location extends to wherever its effects are felt — an interpretation that places South Korea within the investigation's scope, The Korea Times reported.

Tan declined to appear for police questioning and instead submitted a written statement. He also requested that the officers assigned to the case be replaced.

The exit ban application comes as South Korea prepares for June 3 local elections — the same vote that Tan cited as the reason for his return to the country.