Conyers has denied any wrongdoing.
The affidavit backs up the statements Grubbs' cousin Marion Brown previously made and details years of alleged sexual harassment and inappropriate behavior from the pol.
"My legacy can't be compromised or diminished in any way by what we're going through now".
News of Conyers' departure comes amid a firestorm of sexual misconduct allegations made against other members of Congress, including Sen.
Conyers is one of four sitting USA lawmakers hit by allegations of sexual misconduct in the wake of the claims targeting movie mogul Harvey Weinstein, which triggered a torrent of accusations against powerful figures in the worlds of entertainment, media and politics.
Conyers' attorney, Arnold Reed, confirmed that the lawmaker meant retiring effective immediately. "These serial accusers have done this before".More news: City tops in crimes against sr citizens, 2nd against women
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Conyers was rushed to a hospital just as a former aide broke her silence for the first time and spoke on the record about her accusations Conyers sexually harassed her. The report didn't specify how Ian Conyers knew of the congressman's plans. The report also includes four signed affidavits from former staff members.
But amid a drumbeat of allegations he groped or sexual harassed women who worked for him, he faced growing calls to resign from colleagues in the House, including Democratic Leader Nancy Pelosi. The interview on the Mildred Gaddis radio show is still ongoing.
"I think there should be a complete disclosure and revealing to all the citizens in the country what federal legislatures are doing or not doing - and any cost that may have incurred as a result of that", Conyers said.
They said the congressman is entitled to due process. "If we're going to raise this unholy and unlawful guillotine, calling for the head of John Conyers, then (an effort to remove) the president of the United States" must begin, he said. In the political world, it's never that simple. Al Franken (D-MN). Last week, Rep. Blake Farenthold (R-TX) was also publicly named as the first sitting member of Congress known to have used a little-known Congressional account to settle an $84,000 sexual harassment claim brought by his former communications director in 2015.
The elder Conyers, however, continued to deny the allegations leveled against him.
Congress has been reviewing policies on how to handle sexual harassment complaints after a string of cases involving prominent figures in the USA media, Hollywood and politics.
Ian Conyers told the newspaper that his great-uncle - the longest-serving current U.S. House member - "is not resigning".