George Santos will not run for re-election in 2024 after the House ethics committee released a damning report on his conduct.
The panel found the Republican congressman from New York "blatantly stole from his campaign" and exploited "every aspect of his House candidacy for his own personal financial profit".
On social media, Mr Santos called the report a "politicized smear".
Still, he said he would not seek a second term in light of the probe.
"My family deserves better than to be under the gun from the press all the time," Mr Santos wrote in a long post that also called the report biased.
His time in office could end sooner than next November, though.
Three of his congressional colleagues - two Democrats and one Republican - said on Thursday they would introduce measures to expel him from the House.
In its report, the ethics committee, which is split evenly between Republicans and Democrats, found that Mr Santos reported fictitious loans to his political committees in order to induce donors to make further contributions to his campaign.
He then diverted campaign money to himself as "repayments" of those fictitious loans, it found.
According to the report Mr Santos also:
Spent campaign money on Botox treatments, luxury fashion purchases, trips to Atlantic City and Las Vegas, holidays in the Hamptons, and even his own rent
Recorded 37 expenses of exactly $199.99 - one cent below a threshold set by law that requires campaigns to keep receipts
Was "frequently in debt, had an abysmal credit score, and relied on an ever-growing wallet of high-interest credit cards to fund his luxury spending habits"
Hired one of his own companies to work for his campaign. The company, RedStone, paid Mr Santos at least $200,000, which he used to pay credit card debt and make purchases from companies including Hermes, OnlyFans and Sephora
Claimed to own multiple properties and a luxury car. The report states: "At no point does Representative Santos appear to have owned a Maserati, despite telling campaign staff otherwise"
"He used his connections to high value donors and other political campaigns to obtain additional funds for himself through fraudulent or otherwise questionable business dealings," the committee said in the report.
"And he sustained all of this through a constant series of lies to his constituents, donors, and staff about his background and experience."
Mr Santos has often sought to pin the blame for his alleged financial improprieties on his ex-campaign treasurer, but the ethics committee said "he was a knowing and active participant in the misconduct".
The panel said it would not start disciplinary action itself because the process would provide the congressman "with further opportunity to delay any accountability for his actions and could risk interfering with the ongoing criminal prosecution".
It added, though, that his "conduct warrants public condemnation, is beneath the dignity of the office, and has brought severe discredit upon the House".
They referred Mr Santos to the Department of Justice for possible prosecution on additional charges.
Mr Santos has already been indicted on charges that include conspiracy, wire fraud, false statements, falsification of records, identity theft and credit card fraud.
The report led to fresh calls for his expulsion from Congress, a fate very few lawmakers have faced in US history.
Notably, the chair of the ethics committee, Mississippi Republican Michael Guest, said he would personally introduce a measure to expel Mr Santos from Congress on Friday morning.
Two Democrats, Robert Garcia of California and Daniel Goldman of New York, also said they plan to introduce measures soon.
Just two weeks ago, Santos survived a vote to expel him from the House, which requires a two-thirds majority.
Only five federal lawmakers have been expelled in US history, including three during the nation's civil war.
Mr Santos was first elected to the House a year ago.
A self-admitted "terrible liar", he portrayed himself on the campaign trail as "the full embodiment of the American dream": an openly gay child of Brazilian immigrants who rose to the upper echelons of Wall Street before entering the world of politics.
But his story began to unravel even before he was sworn in.
Mr Santos claimed to have been educated at Baruch College in New York City before becoming a "seasoned Wall Street financier and investor" with experience working at prestigious firms including Goldman Sachs and Citigroup. He said his mother narrowly survived the 9/11 attacks, that he had a large real estate portfolio and was a "Proud American Jew".
He later admitted he never graduated from Baruch College or any other university, or worked for Goldman Sachs and Citigroup. Nor did he own property across New York. He is Catholic, not Jewish and his mother was likely not in the US on 11 September 2001.
The ethics committee said his misconduct went far beyond misrepresenting his past, however, and the report also said Santos displayed a "lack of candor during the investigation itself".