U.S. Representative Duncan Hunter arrives at court where he was expected to plead guilty to federal charges stemming from allegations that he and his wife misused campaign funds in San Diego, California, U.S., December 3, 2019.

California Rep. Duncan Hunter who pleaded guilty in federal court to a single felony count of misuse of campaign funds said Friday that he will resign after the holidays.

"Shortly after the Holidays I will resign from Congress. It has been an honor to serve the people of California's 50th District, and I greatly appreciate the trust they have put in me over these last 11 years," Hunter said in a statement.

Hunter, who represents California's 50th Congressional District, and his wife were charged with 60 criminal counts of campaign finance violations in August 2018. They were under fire for allegedly misusing campaign funds on personal items such as vacations, gas and groceries.

His resignation announcement comes a day after the House Ethics Committee sent him a letter advising him to avoid voting in the House of Representatives going forward.

The letter said that his guilty plea brought a rule into effect that says any member who's convicted of a crime whose sentence is at least two years "should refrain from voting on any question at a meeting of the House."

The committee also threatened disciplinary action if Hunter ignores the warning and tries to vote.

"We emphasize in the strongest possible terms that if you violate the clear principles of this provision - that is, for example, by voting in the House - you risk subjecting yourself to action by this Committee, and by the House, in addition to any other disciplinary action that may be initiated in connection with your criminal conviction," the letter said.

Hunter, who will be 43 on Saturday, was first elected to his seat in 2008. He won again last November with 51.7% of the vote, despite facing indictment. The seat has been held by the family for decades, with Hunter's father in the role for 28 years before him.

Hunter had denied any wrongdoing, initially pleading not guilty and labeling his prosecution a "witch hunt."

In an interview with KUSI News when he announced he planned to change his plea, Hunter said, "I think it's important that people know that I did make mistakes. I did not properly monitor or account for my campaign money. I justify my plea with the understanding that I am responsible for my own campaign and my own campaign money."

Margaret Hunter, his wife and former campaign treasurer, took a plea deal earlier this year, admitting to her role in the scandal and agreeing to testify against her husband. That put pressure on the congressman to strike his own deal.

Federal Election Commission finance rules prohibit using campaign funds for personal use.

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