Getty ImagesUS Congressman Eric Swalwell will resign from Congress, after dropping out of the California governor race following growing pressure over sexual misconduct allegations.
"I am deeply sorry to my family, staff, and constituents for mistakes in judgement I've made in my past," the Democrat said in a letter posted on X.
"I will fight the serious, false allegation made against me. However, I must take responsibility and ownership for the mistakes I did make."
Four women accused him last week of misconduct ranging from sexual harassment to rape. In comes as Congress opens an ethics inquiry into Swalwell, who was elected to the House of Representatives in 2012 to a district near San Francisco.
Democrats were already scrambling in California's governor race. Then Swalwell dropped out
Moments after Swalwell's announcement, another congressman facing an ethics inquiry - Texas Republican Tony Gonzales - posted on X that on Tuesday he will "file my retirement from office". Over the weekend, several House lawmakers suggested expelling both Swalwell and Gonzales, who had already dropped his re-election bid after admitting having an affair with an aide.
Swalwell, a married father of three who frequently criticises President Donald Trump, has repeatedly denied the allegations against him.
Within hours of the accusations surfacing on Friday, he lost the backing of prominent supporters for his gubernatorial run and many of his staff members resigned.
Prosecutors in Manhattan then said they were opening a probe into his conduct. On Capitol Hill, the House ethics committee began its own investigation, while Republicans vowed to expel him from the chamber.
In his resignation letter, Swalwell said it would be wrong for fellow lawmakers to expel him "without due process, within days of an allegation being made".
He added: "But it's also wrong for my constituents to have me distracted from my duties. Therefore I plan to resign my seat in Congress."
Swalwell said he plans to "work with my staff in the coming days to ensure they are able, in my absence to serve the needs of the good people" in his district, which stretches east of San Francisco and north of San Jose.
Congress is returning from recess on Tuesday, with the ethics committee planning to take up inquiries into both Swalwell and Gonzales.
Gonzales has admitted to an affair with a staff member who later died by suicide.
Posting on X on Monday, he wrote: "There is a season for everything and God has a plan for us all.
"When Congress returns tomorrow, I will file my retirement from office. It has been my privilege to serve the great people of Texas."
No clear leader has yet emerged in the highly-watched California governor's race from the crowded Democratic field, which risks splitting the vote for the party's candidates in the state's primary in June. Among Democratic candidates, Swalwell had been projected to be one of the frontrunners, according to two opinion polls.
Unlike many states, California holds an "open" primary, meaning voters can select candidates from any party. The top two vote-getters in the primary move on to the 3 November general election regardless of party preference.
That has raised a terrible prospect for Democrats, who currently control the state legislature and governor's mansion: they could be frozen out of November's general election if the two Republican candidates finish ahead of them in June's primary.
On Monday, California election officials confirmed that it is too late to have Swalwell's name removed from voter ballots.
With reporting from Kayla Epstein
