WASHINGTON – The Department of Justice on Wednesday announced that the former chief of staff to then-U.S. Rep. Paul Broun has been indicted in connection with allegedly misusing taxpayer money to finance campaign activities and obstructing a congressional investigation into the matter.

The eight-count indictment charges David Bowser, Broun’s longtime top staffer, with one count of obstruction of proceedings, one count theft of government property, one count of concealment of material facts and five counts of making false statements.

Bowser's arraignment and initial appearance have yet to be scheduled. The Justice Department said the FBI is investigating the case.

Bowser, now the chief of staff to U.S. Rep. Mimi Walters, R-Calif., did not respond to requests for comment.

The announcement came seven months after former GOP strategist and debate coach Brett O'Donnell pleaded guilty in U.S. District Court in Macon to lying to investigators about his relationship with Broun's office.

O’Donnell listed Bowser as “Person A” and Broun as “Congressman A” in his plea, details that matched up with an Office of Congressional Ethics investigation that named both men. Bowser was quoted in the plea for telling O’Donnell that the Office of Congressional Ethics can go “f—- themselves” and that consultant should falsely maintain that he was a volunteer debate coach for Broun’s campaign.

Official funds for members of Congress cannot go toward campaign activity, though official staff often volunteer for campaigns in their free time. Many staffers also are paid by a member’s campaign and official accounts, and Broun did this for some staff but not O’Donnell. The debate coach was paid $43,750 from 2012 to 2014 from Broun’s taxpayer-funded office account, and he performed similar services for other members of Congress.

Bowser and Broun both told investigators and said publicly that O’Donnell worked for Broun from 2012 to 2014 as a consultant for $2,500 per month to help sharpen Broun’s communications skills on official matters such as floor speeches, while volunteering for Broun’s 2012 House re-election campaign and 2014 Senate bid.

The case has marked the first time someone has been charged with lying to the Office of Congressional Ethics, a quasi-independent body that refers cases to the member-run U.S. House Ethics Committee.

Broun said he is "disappointed" about the indictment and added that he is "not aware of any ethical violations by my staff at any time."

"I have cooperated fully with the investigators at every step. Throughout this process, it was made clear that I was not the subject of the investigation. Everything I did was completely above board and the investigation has proven that," Broun said in a statement.

The news comes seven weeks before Republican primary voters in Georgia’s ninth congressional district hit the polls. Broun, a tea party favorite, is running against incumbent Doug Collins, R-Gainesville, for the northeast Georgia seat.

The indictment has already become a campaign issue for Broun.

"All roads in this criminal case lead back to Paul Broun. When is he going to take responsibility for abusing taxpayers hard earned money?" said Collins Campaign Manager Carmen Foskey.

Broun shot back, "I find it also disappointing that Mr. Collins would politicize this event in Mr. Bowser's life and seek to use it for his political gain."

The House Ethics Committee investigation looking into the matter ended in January 2015 when Broun left office after he finished fifth the Republican primary for U.S. Senate the year before. It could be revived if Broun wins the May 24 primary and later the general election.

In his eight years in Congress, Broun gained a reputation as one of the most conservative voices in the Republican Party. He waged constant battles to reduce government spending and enact anti-abortion provisions and was often a thorn in the side to House GOP leaders. He was one of 12 House Republicans to vote against John Boehner for a second term as speaker in 2013.