Donald “D.A.” Jones pleaded guilty to charges of lying to federal agents and agreed to cooperate in the investigation, the Philadelphia Inquirer reported.
Jones and fellow Brady aide Ken Smukler were charged in October with making illegal campaign contributions on Brady’s behalf to a 2012 primary opponent, former Philadelphia Municipal Court Judge Jimmie Moore.
Moore later pleaded guilty to hiding the $90,000 payment.
Jones’ plea is the first admission of guilt to come from Brady’s camp.
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“I accept full responsibility for my actions and consider my guilty plea a first step in making amends,” Jones said in a statement through his attorney. “I apologize to the people of Philadelphia and to my family for bringing this dishonor upon them.”
In a deal struck by prosecutors, Jones agreed to testify against Brady or Smukler if necessary.
On Friday, Jones admitted to U.S. District Judge Jan E. DuBois that he conspired to hide payments to Moore that were offered as an incentive to get him to drop out of the Democratic primary.
The plea document said that Jones and Smukler agreed to help Moore retire some of his campaign debt, including by funneling $25,000 from Jones’ consulting firm to Moore’s campaign manager, Carolyn Cavaness.
Prosecutors say Smukler provided the additional $65,000 through his consulting company and disguised it as money for polling data.
But Smukler denied the charges against him.
Brady’s lawyers, Jamie Eisenhower and Ronald Levine, have repeatedly said their client did nothing wrong and declined to comment after Jones’ plea.
Justice Department lawyers allowed a series of agreements Brady had signed extending the five-year window in which he could be charged to expire last month. Those extensions allowed the FBI to continue to investigate Brady but also gave Brady’s lawyers more time to convince investigators the Pennsylvania Democrat had done nothing wrong.