The former chief prosecutor has spent his first few months in office determined to enhance the role of prosecutors in the government. He has appointed many of his former prosecutor colleagues to senior posts in the presidential office.
Meanwhile, prosecutors are investigating the alleged "forced repatriation" of North Korean fishermen in 2019 in what is seen by critics as an attempt to go after Yoon's predecessor, former President Moon Jae-in.
The Yoon administration has also launched a controversial measure to give the Ministry of the Interior and Security oversight over key functions by the National Police Agency, threatening to erode its recently acquired authority over criminal investigations that was held previously by the prosecution service. Critics claim the police are at risk of losing their autonomy as an independent agency and becoming vulnerable to political pressure.
The recent series of actions highlights once again the immense power that has been wielded by the prosecution service, which traditionally has enjoyed exceptional influence in Korea unparalleled in other advanced democracies.
Korea's prosecution was one of the few government agencies that did not undergo significant reforms after the end of military rule in the late 1980s. It can investigate corruption and economic crimes unilaterally.
Over the decades, both conservative and liberal Korean presidents have weaponized probes by prosecutors to conduct vendettas against political opponents and rivals. It is one of the reasons why several former presidents have either been investigated or jailed on corruption charges once they left office.
Yoon appears to be attempting to turn back the clock on recent efforts by the Moon administration to curb the power of the public prosecutors' office by distributing some of its powers to other agencies. He is seeking to have the Constitutional Court overturn laws to reform the prosecution service that were passed by the National Assembly in the last two years.
The irony is that Moon is partly to blame for the current situation. He appointed Yoon as the prosecutor general in 2019 after he helped convict President Park Geun-hye, Moon's predecessor, for corruption and abuses of power. Conservatives at the time accused Moon of using the prosecution for his own political purposes.
However, Moon appointed Cho Kuk as justice minister, shortly after Yoon's promotion, to limit the investigative powers of prosecutors by creating a new agency to probe crimes by senior officials and top businessmen.
Within days, prosecutors indicted Cho's wife for hiding assets using forged documents, for which she was later convicted and Cho was forced to resign.
The episode probably helped the prosecution office in the defense of its powers since it exposed would-be reformers as political hypocrites. But it also appeared to confirm public perceptions that the prosecution wielded too much power and abused it.
The feud between the Moon administration and the prosecutors escalated when Choo Mi-ae, Cho's successor, suspended Yoon as chief prosecutor in late 2020, accusing him of lacking political impartiality and allegedly spying on judges dealing with the trial involving Cho's wife.
Yoon resigned in March 2021 to pursue his presidential ambitions. His confrontations with Moon's justice ministers endeared him to the conservative opposition and helped him win the nomination of the People Power Party, which was seeking a "clean" candidate after the corruption scandal involving Park Geun-hye.
The political infighting over the role of the prosecution office during the last several years threatens to do lasting damage since it has undermined public confidence in government institutions.
The controversy has exposed both how the executive branch has manipulated prosecutors for political advantage and how prosecutors can use their own powers to set the political agenda by conducting vendettas against government officials who oppose them.
Now that Yoon is in power he can claim that Moon's prosecution reforms were just an attempt to prevent investigations of the former president's associates for possible criminal behavior. The prosecution seems emboldened to conduct new probes of its liberal critics, including possibly Moon.
Although Yoon campaigned by promising a return to the rule of law, his actions could contribute to the increased politicization of the justice system.
Belief in democracy is bolstered by public faith in the neutrality of government institutions. If partisan allegiance is seen as trumping personal integrity, it undermines democracy.
Koreans only need to look to the U.S. to see how increased partisanship is eroding legal norms there. The recent FBI search of former President Donald Trump's property has sharply divided the nation. His supporters say the FBI exceeded its authority while Trump's opponents said the search was a legitimate action to uncover possible crimes. This division is leading to predictions of increased political violence in the future.
John Burton (johnburtonft@yahoo.com), a former Korea correspondent for the Financial Times, is a Washington, D.C.-based journalist and consultant.