A Missouri attorney set to join the state's House of Representatives has accused a fellow lawmaker of sexually assaulting her during a meeting in August. Cora Faith Walker wrote a letter to Missouri House Speaker Todd Richardson asking him to prohibit Steven Roberts Jr from taking his seat in the Legislature after accusing him of rape.

"Earlier this week, I reported a sexual assault to the St Louis Metropolitan Police Department," Walker wrote. "I named my rapist as Steven Roberts, Jr., who hopes to be in the Capitol next year as the Representative of the 77th District."

In the letter, 31-year-old Walker claims she was sexually assaulted by Roberts after meeting with him at a St Louis flat on 26 August, 2016. Walker said she had two glasses of wine, does not remember the rest of the night and woke up the next morning in a bed.

According to CBS News, Walker said she told her husband but the couple waited several weeks before reporting the incident to police.

Walker wrote that she initially reported the alleged rape anonymously but "ultimately decided to press charges, in the interest of my own safety and the safety of others."

According to the St Louis Post-Dispatcher, which first reported the incident, Walker asked that her name and story be used "to give courage to women who are victims of rape, and to encourage a change to the Jefferson City environment that 'perpetuates gender violence and rape culture.'"

Roberts' attorney, Scott Rosenblum, confirmed the allegations were being investigated by police, reports the Associated Press.

The AP also says that Roberts has not been arrested or charged. "I think that we will be able to basically undermine those allegations pretty quickly," Rosenblum said.

"Whatever happened between these individuals was absolutely consensual and I think we have what I would call objective evidence to support that."

Walker and Roberts are both Democrats who are running unopposed and expect to be sworn in in January, the Washington Post reported.

Richardson confirmed he had received Walker's letter in a written statement to CBS St Louis LMOX NewsRadio.

"The kind of conduct alleged cannot be tolerated in our state and will not be tolerated in the House of Representatives. While the House has no jurisdiction over non-members, we will monitor the criminal investigation closely and continue to have a zero tolerance policy for sexual assault, misconduct and harassment., he said.