Gov. Robert F. McDonnell talks with the media after participating in a roundtable discussion at T.C. Williams High School on Aug. 15 in Alexandria. (Jahi Chikwendiu/The Washington Post)

Private attorneys representing the office of Virginia Gov. Robert F. McDonnell and other government officials grappling with federal and state investigations of McDonnell’s interactions with a wealthy political benefactor have now charged taxpayers more than $575,000.

According to invoices released by McDonnell’s office Friday, two private firms representing McDonnell and his staff racked up more than $331,000 in fees in July, August and September.

That came on top of $244,000 the firms had charged earlier in the summer.

McDonnell (R) has separately hired a legal team to defend him against an ongoing federal grand jury probe, a defense team being paid through a private fund established by supporters.

But taxpayers are footing the bill to provide legal counsel to staff members who have been interviewed as part of the investigations or whose records have been seized.

McDonnell spokesman Tucker Martin stressed that the firms are not representing McDonnell in his personal capacity, the selection of the firms was approved by the attorney general and the attorneys are offering their services at discounted rates.

“Virginia law provides for situations in which outside counsel must be appointed due to the Office of the Attorney General determining that it has a conflict in a specific case. That is what has occurred in this situation,” Martin said.

Federal authorities are investigating whether McDonnell improperly assisted Jonnie R. Williams Sr., the chief executive of a dietary supplement company, in exchange for gifts and loans. Williams provided the McDonnell family more than $160,000 in gifts and money in 2011 and 2012 that the governor has said were loans.

McDonnell has apologized for embarrassing the state through his interactions with Williams. But he has said Williams’s company, Star Scientific, received no special treatment.

The two firms representing the governor’s office are part of a network of lawyers appointed to various state agencies as part of the case.

Private counsel has also been appointed to represent employees at Virginia Commonwealth University, where researchers received grants to study Star Scientific’s supplement in 2011, and to represent the Virginia State Police and, separately, the state police investigator working the case alongside the FBI.

But the bulk of the taxpayers’ bill is going to the two firms representing the governor and his staff.

According to the heavily redacted invoices, former Democratic state attorney general Tony Troy and other members of his firm, Eckert Seamans Cherin & Merlot, spent nearly 662 hours on the case in July and August.

They charged up to $250 an hour for their time, and the firm collected $148,359 for the two months. Troy was first appointed in May.

A bill for Troy’s work in September was not released, nor were any bills for October.

The firm Baker & McKenzie was added to the case to represent staff for the governor in July. In August and September, three lawyers for the firm worked 431 hours and the firm earned $182,806. The firm is charging the state up to $450 an hour for its work.

Providing official legal counsel to the governor’s office would ordinarily be a job for Attorney General Ken Cuccinelli II (R).

But Cuccinelli has said he has a conflict of interest in the case.

The Star investigation apparently grew out of a separate criminal probe of the chef at the governor’s mansion.

Chef Todd Schneider was accused of stealing food from the kitchen. In response, he told investigators that he was aware of other wrongdoing at the mansion, including the relationship between the McDonnells and Williams.

Cuccinelli said it would be a conflict for him to represent state employees responding to those charges since he was also prosecuting the chef. Cuccinelli appointed a special prosecutor to handle the matter in May; in September, Schneider pleaded no contest to two misdemeanors.