SEOUL - South Korea's opposition parties on Tuesday submitted a bill to appoint a special counsel and investigate the alleged political corruption involving the impeached President Yoon Suk-yeol and his wife, Kim Keon-hee.

The main liberal opposition Democratic Party and five other minor parties proposed the bill to let the independent prosecutor look into the allegations that Yoon and Kim were implicated in illegal public opinion manipulation during the 2022 presidential election in which Yoon was elected president.

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A self-proclaimed political broker, Myung Tae-kyun, was suspected of providing fake and free opinion polls in return for various interests, such as his interference in the nomination of a lawmaker candidate of the ruling People Power Party.

Yoon and Kim were believed to have illegally intervened in the ruling party's candidate nominations for local elections and by-elections in 2022 and parliamentary elections in 2024.

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Myung was indicted under detention on Dec 3 last year when Yoon declared an emergency martial law, but it was revoked by the opposition-led National Assembly hours later.

The Democratic Party estimated that Myung's indictment may have triggered Yoon's martial law imposition.