The Seoul High Court this week postponed the trial of Lee Jae-myung, the opposition Democratic Party's presidential candidate, until after the June 3 election.

The court's decision on Wednesday is the latest twist in a political drama that has divided South Korea since the now-impeached former president Yoon Suk Yeol of the conservative People Power Party (PPP) briefly declared martial law in December last year.

"It is obviously critical that legal procedures be followed in all cases, but the situation in South Korean politics is extremely volatile at the moment and I believe the court ruled this way as they believed it would best preserve stability," Park Jung-won, a professor of law at Dankook University, told DW.

Critics, however, say the ruling could deal a mortal blow to the PPP and effectively guarantees that Lee will win the election in June. 

What charges is Lee facing?

Lee is accused of violating election laws in a previous campaign by deliberately spreading "false information" to voters during campaigning for the 2022 election, which Lee narrowly lost.

The case is one of five that he is currently fighting. In addition to the alleged election law violation, he is accused of perjury, breach of trust, unauthorized money transfer to North Korea, and embezzling public funds.

In South Korea, a candidate is barred from running for office for 10 years if they are found guilty in a legal case and fined a minimum of 1 million won ($714, €630).

Lee was initially convicted in November 2024 and given a one-year suspended prison sentence, which would have ended his presidential ambitions.

He appealed to the Seoul High Court, which ruled in his favor in March, and got his campaign back on track.

But prosecutors then appealed that ruling to the Supreme Court, which on May 1 overturned Lee's acquittal and instructed the high court to go ahead with the trial.

The first hearing in the case had been scheduled for May 15, until the court announced it was postponing the first hearing until June 18 — two weeks after the presidential election.

'Threat to democratic foundations'

The apparent pressure that the Democratic Party (DP) has put on the judiciary has been criticized in South Korean media.

An editorial in the Korea JoongAng Daily on May 5 said the opposition's reaction to the May 1 Supreme Court ruling —  the DP decried it as a "judicial coup" and threatened to impeach the chief justice of the court — has "escalated to a level that raises serious concerns about democratic norms."

It added that continuing to "undermine the judiciary […] poses a grave threat to Korea's democratic foundations."

Shortly before the Seoul High Court's ruling on Wednesday, the Korea Times accused the DP of "a clear violation of the principle of separation of powers" by demanding that Lee's trial be postponed.

It also accused the DP of double standards, as the party demanded that Yoon Suk Yeol accept the Supreme Court's decision to impeach him, but is now challenging the courts in support of its own candidate.

The PPP "will be angry and will protest" the decision, law professor Park said, but the party remains broadly unpopular with the electorate after Yoon's martial law declaration and his subsequent arrest for insurrection.

His case is ongoing, while the party that he used to lead has been squabbling over whom to appoint to run against Lee. The PPP eventually nominated Kim Moon Soo on May 3.

"What conservatives find terrifying is that if Lee wins the election, the Democratic Party will hold the presidency and a super-majority in the national assembly, and I expect they will use that to threaten the autonomy of the judiciary," Park said.

'No obstacles' to Lee presidency

One of the first actions that Lee is likely to take after a potential victory on June 3 would be a bill that prevents the courts from continuing with a trial against a president-elect, acording to Lee Sang-sin, a research fellow specializing in political science at the Korea Institute for National Unification.

He told DW that "the constitution is ambiguous on whether a president can still face proceedings."

"One interpretation of the constitution is that all legal cases must stop during a presidency, while the alternative interpretation is that if a trial has commenced — as it has with Lee — then it can continue," he said.

The expert highlighted that there are "no obstacles" on Lee's path to victory at the ballot box, especially given the PPP's struggles to appoint a candidate and move on from the martial-law fiasco caused by its former leader Yoon.

He also said that Lee's legal troubles have not dented his support among voters, which "remains solid" even after the Supreme Court ruling.

"If anything, it mobilized his supporters even more," the expert added.

And while the debate among legal scholars continues, Lee Sang-sin believes that, if the DP candidate Lee wins the election as is widely expected, the legal cases against him will be dropped or shelved.

"It seems that with this ruling, Lee is completely free of his legal issues," he said, adding that most South Korean voters "will see this as the turning point in the election, and that it is effectively game over."

Edited by: Karl Sexton