Rep. Duncan Hunter accused of using campaign funds to lead 'series of intimate relationships' outside his marriage

Embattled Rep. Duncan Hunter, who is accused of allegedly using hundreds of thousands of dollars in campaign funds for personal use, allegedly tapped into some of that money to also finance romantic trysts with multiple congressional aides and lobbyists, according to federal prosecutors in new court filings.

In documents filed Monday, federal prosecutors detailed allegations against Hunter, saying that he used thousands of dollars in campaign funds to pay for alcohol, romantic getaways to Lake Tahoe, golf outings and Uber rides to carry out "a series of intimate relationships" with individuals identified as numbers 14, 15, 16, 17 and 18.

In one instance, prosecutors said Hunter and "Individual 14" spent a January 2010 weekend together at a ski resort near Lake Tahoe, skiing and ordering room service. When the weekend ended, court documents allege, Hunter paid the $1,008 hotel tab using campaign funds from his campaign credit card.

Prosecutors said that at that time, Hunter's personal bank accounts "had a negative balance," suggesting that "he could not have paid for the weekend without dipping into campaign funds."

"Hunter's intimate relationships furnished part of his motive to embezzle from the campaign," court documents said. "Carrying out all these affairs did not come cheap...Given the pronounced financial difficulties the Hunters were facing, his use of campaign funds to pursue these relationships was necessary for Hunter to satisfy his desire for intimacy."

In an August 2018 letter to Deputy Attorney General Rod J. Rosenstein, a lawyer for Hunter accused the U.S. Attorney's Office for the Southern District of California of political bias against the representative, writing: "While there may be evidence of infidelity, irresponsibility or alcohol dependence, once properly understood, the underlying facts do not equate to criminal activity; these allegations are, however, intended to embarrass and humiliate the congressman shortly before a crucial election and also alienate him from his wife."

The accusations revealed Monday came just days after the Rep. Hunter’s wife, who also faces charges that she used hundreds of thousands of dollars of campaign donations along with Duncan Hunter to pay for personal expenses, changed her plea with the court.

On Thursday, Margaret Hunter, who worked as her husband's campaign manager, pleaded guilty to one count of conspiracy to defraud the U.S. in exchange for her testimony and cooperation with prosecutors -- possibly setting the stage for her testify against her spouse.

Margaret Hunter had initially pleaded not guilty to all charges.

In a statement to the Associated Press on Thursday, Duncan Hunter said the indictment was meant to inflict "as much political damage as possible."

"It was politically motivated at the beginning, it remains politically motivated now," he told the AP.

In August 2018, both Duncan Hunter and Margaret Hunter were indicted by a federal grand jury in San Diego on charges that they converted more than $250,000 in campaign funds to pay for personal expenses, and filed false campaign finance records with the Federal Election Commission.

The 48-page indictment alleges that the Hunters illegally used campaign money to pay for expenses that they could not otherwise afford from 2009 through 2016. The purchases allegedly included family vacations to Italy, Hawaii, Phoenix and Boise, Idaho; school tuition; dental work; theater tickets; and domestic and international travel for almost a dozen relatives.

The Hunters also allegedly spent tens of thousands of dollars on smaller purchases, including fast food, movie tickets, golf outings, video games, coffee, groceries, home utilities and expensive meals, according to the indictment.

To allegedly conceal their personal spending, the Hunters mischaracterized the purchases in FEC filings as "campaign travel," "dinner with volunteers/contributors," "toy drives," "teacher/parent and supporter events," and other false descriptions, according to the indictment.

The House Ethics Committee was investigating allegations of Hunter's improper use of campaign funds, but announced in March 2018 that it would continue to defer to the Department of Justice investigation.

Duncan Hunter has maintained in the past that he was not aware of the improper spending, and that he'd repaid his campaign committee roughly $60,000 to cover the expenses.

A plainspoken former Marine, Duncan Hunter has served in Congress since 2009, after replacing his father who was retiring, former House Armed Services Committee Chairman Duncan Hunter. He was one of the first lawmakers to endorse President Donald Trump's 2016 campaign.

His trial is scheduled for Sept. 10.

ABC News' Mike Levine, Bill Hutchinson and Benjamin Siegel as well as The Associated Press contributed to the reporting in this story.