WASHINGTON -- A local public relations consultant pleaded guilty in federal court on Tuesday to charges that she helped facilitate a campaign finance scheme that illegally steered $653,000 to the benefit District of Columbia Mayor Vincent Gray's 2010 campaign.

In Eugenia Clarke Harris' plea agreement, federal prosecutors acknowledged the existence of a shadow campaign to elect Gray, The Washington Post reports.

An assistant U.S. attorney, according to the Examiner, said Gray's campaign used the unreported funds to boost its get-out-the-vote efforts.

Harris, who admitted guilt in one of the largest straw donation schemes in D.C. campaign politics, was not alone, according to prosecutors.

The Post reports:

Prosecutors have not publicly identified the co-conspirator, but three persons familiar with the probe have said the person is Jeffrey E. Thompson, owner of two companies that do significant D.C. government business. Thompson has not been charged.

Federal agents raided Thompson's office and house in March.

Two other Gray campaign aides have previously pleaded guilty to charges related to the 2010 campaign's operations.

A statement of offense, according to DCist, said that "Harris also attempted to destroy evidence of the scheme, and lied on her tax returns to conceal the fact that she was using two of her businesses to funnel money to the shadow campaign."

Harris' guilty plea was not the only legal proceeding involving the mayor on Tuesday. Washington City Paper notes that Gray was in court giving a deposition related to a federal probe into a D.C. Lottery contract.

Gray, who has denied the various allegations, did not make public comments on the matter on Tuesday.

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  • Presumptive mayor-elect Vince Gray rallys fellow Democrats during a 'get out the vote' campaign event at the First Trinity Lutheran Church Oct. 14, 2010, in Washington, D.C.

  • Newly elected Mayor Gray delivers the winning speech of the election in front of his supporters at Love Nightclub on Nov. 2, 2010.

  • Mayor Gray

    Mayor Gray and Debra Lee speak during the 4th annual BET Honors at the Warner Theatre on January 15, 2011.

  • Vincent Gray

    Gray with members of the Urban Land Institute, celebrating the group's 75th anniversary on Dec. 14, 2011.

  • Vincent Gray

    Breaking ground at Cardozo Senior High School, Nov. 11, 2011.

  • Vincent Gray

    Gray with former Office of Aging Director Veronica E. Pace at the opening of the new Office of Aging Headquarters on Oct. 27, 2011.

  • Vincent Gray

    The mayor bagging groceries at Safeway during a breast cancer fundraiser on Oct. 25, 2011.

  • Vincent Gray

    Mayor Gray at DCOA's Senior Citizen Holiday Celebration on December 8, 2011.

  • Vincent Gray

    Celebrating Nordic Food Day with students at Miner Elementary School, Oct. 26, 2011.

  • Vincent Gray

    Gray marching at the D.C. Full Freedom Rally on Oct. 15, 2011.

  • Vincent Gray

    Gray meeting with Mohammad Iqbal Aziz, governor of Laghman Province in Afghanistan, on Nov. 2, 2011.

  • Vincent Gray

    Gray at a pizza party honoring local youth football players on Dec. 13, 2011.

  • Vincent Gray

    The mayor addresses an audience at the Cadillac display at the 2011 Washington Auto Show Jan. 27, 2011 at the Washington Convention Center.

  • Vincent Gray

    Gray with Planters mascot Mr. Peanut at The Corps Network 'Plant' New Urban Park on July 12, 2011.

  • Vincent Gray

    District of Columbia Mayor Vincent Gray takes questions as he testifies in support of a House resolution expressing support for admitting the District of Columbia as the 51st state., Jan. 27, 2012, in Concord, N.H.

  • Vincent Gray

    Gray chats with President Obama following his annual back-to-school address at Benjamin Banneker Academic High School Sept. 28, 2011.

  • Vincent Gray And Cathy Lanier

    Mayor Gray and Metropolitan Police Department Chief Cathy Lanier during a news conference on April 10, 2012, to announce initiatives to combat the growing robbery rate targeting smartphones and other cell phones.

  • Vincent Gray

    Gray arrives at the opening gala of the historic Howard Theater in Washington, D.C. on April 12, 2012.

  • Vincent Gray With Mary Cheh

    The mayor showcasing the city's newly-purchased snowplows on Dec. 14, 2011, with D.C. Councilmember Mary Cheh (D-Ward 3).

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