President Yoon Suk Yeol poses with new Prosecutor General Shim Woo-jung after presenting him with a letter of appointment at the presidential office in Seoul, Wednesday. Yonhap

Shim Woo-jung, Korea's new prosecutor general, faces an uphill battle handling various politically sensitive cases, including allegations against first lady Kim Keon Hee and former President Moon Jae-in, all while trying to restore public trust in the country's scandal-ridden judicial system, according to political watchers, Wednesday.

The former vice justice minister stressed the importance of upholding legal principles and maintaining political neutrality.

"I will do my best to abide by the independence of the prosecution and neutrality from political influences. The prosecution will investigate according to legal principles based on evidence without any other considerations," Shim said during a National Assembly confirmation hearing on Sept. 3.

Shim, who assumed the office on Monday, is tasked primarily with completing the investigation into the luxury gift case involving the first lady.

The investigation review panel of the Supreme Prosecutors' Office, comprising 15 outside experts, recommended against indicting Kim on Sept. 6, concluding that her acceptance of a Dior bag and other gifts from Korean American pastor Choi Jae-young in 2022 was not related to President Yoon Suk Yeol's official duties.

The panel's decision came after prosecutors at the Seoul Central District Prosecutors Office decided to drop graft, bribery and other charges against the first lady following a four-month inquiry.

However, Choi, who insisted that the gifts were given to Kim in hopes of receiving favors, requested the review committee examine criminal charges. The committee is expected to convene for deliberation on Choi's case on Tuesday, and prosecutors are expected to finalize a decision clearing the first lady of her charges.

Another challenge that lies ahead is the probe into the first lady's alleged involvement in manipulating the stock price of Deutsch Motors, a licensed BMW dealership in Korea, between 2009 and 2012.

Last Thursday, the Seoul High Court convicted a man, identified only by his surname Son, of aiding and abetting a stock manipulation scheme involving Deutsch Motors. He was sentenced to six months in prison, suspended for one year. The court also upheld the conviction of Kwon Oh-soo, former chairman of Deutsche Motors, for using insider information to induce purchases of the company's stocks. The court sentenced Kwon to three years in prison, suspended for four years. He was also fined 500 million won ($376,843).

The ruling is likely to pose legal challenges for Kim, who was accused of allowing the stock-price manipulators to use her bank accounts.

Former President Moon Jae-in, right, and Rep. Lee Jae-myung, leader of the main opposition Democratic Party of Korea, hold their arms up at Moon's home in Yangsan, South Gyeongsang Province, Sept. 8. Yonhap

An investigation into bribery allegations involving Moon is expected to ignite a political firestorm. Prosecutors have identified the former president as a suspect in a bribery case, alleging that his former son-in-law received preferential treatment in securing a job at Thai Eastar Jet in exchange for arranging a government position for the low-cost carrier's founder.

The Jeonju District Prosecutors' Office is leading the investigation into Moon's potential involvement in the bribery case. Separately, the Seoul Central District Prosecutors' Office is investigating an allegation that former first lady Kim Jung-sook, Moon's wife, spent a large sum of taxpayer money to fund her solo trip to India in 2018. The opposition parties have decried the accusations as "politically motivated."

In a counterattack against prosecutors, the main opposition Democratic Party of Korea (DPK) has been attempting to impeach the prosecutors involved in the bribery probe into Moon.

The move comes after the DPK called for impeaching four prosecutors, including those involved in the corruption investigation into Rep. Lee Jae-myung, the party chairman who has been indicted on charges of corruption and breach of trust. The DPK is also looking to pass a bill mandating a special counsel probe targeting the first lady at today's plenary session.

"Let's concentrate our efforts so that the prosecution can fulfill its duty of protecting citizens from crimes," Shim said in the remarks on his first day of work.

His appointment ceremony is scheduled for Thursday.