ST. LOUIS (Reuters) - A St. Louis judge on Thursday dealt Missouri Governor Eric Greitens another legal setback in the sex scandal embroiling his office, refusing to dismiss a criminal invasion of privacy charge stemming from an admitted extramarital affair.

FILE PHOTO: Missouri Governor Eric Greitens appears in a police booking photo in St. Louis, Missouri, U.S., February 22, 2018. St. Louis Metropolitan Police Dept./Handout via REUTERS

The decision by Judge Rex Burlison paved the way for the single-count felony case against Greitens, a Republican under mounting pressure from both parties to resign, to proceed to trial even as he comes under scrutiny for unrelated accusations of computer tampering.

Greitens’ lawyers last week sought to throw out the privacy case on grounds of prosecutor misconduct, saying St. Louis Circuit Attorney Kim Gardner, a Democrat, had tried to conceal video evidence supporting the governor and his assertions that the affair was entirely consensual.

The videotape in question was a lengthy deposition interview of the woman involved, a hair stylist identified in court documents only as “K.S.,” conducted by Gardner in January.

Defense lawyers said prosecutors deliberately withheld the tape, in violation of pretrial discovery rules, until just after a special Missouri state House panel issued a report of its own last week, detailing the woman’s sworn testimony to the committee accusing Greitens of abuse, blackmail and sexual coercion.

Prosecutors said technical glitches with the deposition video kept them from furnishing it sooner, and they argued that the defense bid for dismissal was a diversionary tactic.

The judge ultimately refused to throw out the case, but ordered new depositions of some witnesses. He also rebuked prosecutors for what he called their “sanctionable” mishandling of evidence.

The invasion of privacy indictment against Greitens accused him of taking a photo of the alleged victim in a state of undress without her consent and making it accessible by computer to use as retaliation should she divulge their relationship.

The alleged offense occurred in March 2015, the year before Greitens, a married father of two and former U.S. Navy SEAL commando, was elected governor. If convicted, he faces up to four years in prison.

Greitens has denied any criminal wrongdoing. Instead, he has cast himself as the victim of a “political witch-hunt” for private transgressions that have nothing to do with his job as governor.

His lawyers have noted that the alleged photograph has never been produced. The woman testified to state lawmakers that she believes the picture was taken while she was bound, blindfolded, and partially nude in Greitens’ basement.

Release of their report on April 11 heightened the calls of Missouri politicians, Democrats and Republicans alike, for Greitens’ ouster. He has vowed to remain in office while he fights to clear his name in court.

The backlash grew more intense on Tuesday after Missouri Attorney General Josh Hawley said he had uncovered evidence of electronic theft of a charity donor list by Greitens, which the governor dismissed as “ridiculous.” That case also has been referred to Gardner.

Hawley, a Republican candidate for the U.S. Senate, has joined Missouri’s top three House Republican leaders in calling for Greitens’ ouster.