The 37-year-old Lee has been accused of receiving sexual services paid for by Kim Sung-jin, CEO of tech company I-kaist, in 2013 and attempting to cover it up by promising to pay off a whistleblower.
Kim's side claimed Lee had promised to set up a meeting with then President Park Geun-hye in return. Lee was considered close to Park at that time, because she had handpicked him for a seat on the party's collective leadership two years earlier.
Due to the scandal, Lee's party membership was suspended for six months by the party's ethics committee in early July, resulting in his ouster from the party chairmanship.
The Seoul Metropolitan Police Agency in charge of the case has determined Lee is not punishable for the alleged bribery since the seven-year statute of limitations had expired, police officials said.
Police are, meanwhile, carrying on with an investigation into other allegations involving Lee, including the alleged cover-up attempt. (Yonhap)