Over a six-month period in 2017 and 2018, nine lawmakers — eight men and one woman — were forced out of office, either by resignation or by early retirement, over varying degrees of allegations of inappropriate sexual behavior or tolerance of such behavior.

At the height of the #MeToo era, then-Speaker Paul Ryan, R-Wis., and then-Minority Leader Nancy Pelosi, D-Calif., directed lawmakers to come up with a new set of rules intended to change the culture of Capitol Hill.

One of the changes, advocated by Rep. Bradley Byrne, R-Ala., updated House rules to prohibit lawmakers from having sexual relations with anyone who works in their congressional office or on any committees on which they serve. The new rules do not apply to relations between lawmakers or with aides they do not supervise. The House approved the change in February 2018.

The first lawmaker to trigger those new rules is a woman, freshman Rep. Katie Hill, D-Calif., and a member of House Democratic leadership.

She is accused by her husband, amid a rancorous divorce proceeding, of having a relationship with Graham Kelly, her legislative director. The conservative media outlet Red State was the first to report on the allegations last week. Hill has publicly and privately denied the allegation and says she is the victim of a smear campaign.

"Allegations that I have been involved in a relationship with Mr. Kelly are absolutely false," Hill said in a statement. "I am saddened that the deeply personal matter of my divorce has been brought into public view and the vindictive claims of my ex have now involved the lives and reputations of unrelated parties."

However, the allegation was enough for the House Ethics Committee to announce a preliminary investigation on Wednesday, citing the 2018 rules change.

The divorce proceedings and the inquiry puts Hill, a rising star in the freshman class, in a rare negative spotlight on Capitol Hill. She was elected by her freshman colleagues to serve as one of their representatives at the leadership table with House Speaker Pelosi. She also serves as the vice chair of the House Oversight and Reform Committee.

Last week, Red State published text messages and nude photos of Hill that revealed select details in the contentious ongoing divorce from her husband, Kenny Heslep, including details of a former consensual extramarital relationship between the two and a female campaign aide.

Hill sent a letter to her constituents on Wednesday admitting to, and apologizing for, the affair with the campaign aide. She also said she is fully cooperating with the Ethics Committee's inquiry.

There are no laws or House rules that prohibit consensual relationships with campaign staffers.

Separately, Hill released a statement saying she notified Capitol Hill Police about the nude photos and they "are investigating the situation and potential legal violations of those who posted and distributed the photos, and therefore will have no further comment on the digital materials." Hill said she is the victim of a targeted political attack. "This coordinated effort to try to destroy me and people close to me is despicable and will not succeed. I, like many women who have faced attacks like this before, am stronger than those who want me to be afraid," she said.

Party leaders have not commented on the allegations against Hill. At least one House Republican, Florida's Matt Gaetz, defended her on Twitter, calling it "absurd" that the Ethics Committee was conducting an investigation. "Who among us would look perfect if every ex leaked every photo/text? Katie isn't being investigated by Ethics or maligned because she hurt anyone - it is because she is different," Gaetz said. Hill is openly bisexual.

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