Former Virginia Gov. Bob McDonnell and his wife Maureen arrive at federal court for a motions hearing in Richmond, Va. on Feb. 3. (Steve Helber/AP)

Federal prosecutors pursuing a corruption case against former Virginia governor Robert F. McDonnell and his wife said Monday they should not have to turn over grand jury instructions, casting defense attorneys’ effort to obtain the materials as something of a publicity stunt.

In a strongly-worded filing, prosecutors wrote that such proceedings are secret and that the defense used its request, which asserts the couple’s innocence, “to castigate the Government on the day the grand jury returned the Indictment, all without so much as articulating the legal standard for the relief they purport to seek.”

“The defendants’ legal argument boils down to an assertion that they cannot be guilty of the charges contained in the Indictment, and therefore, the Court should examine any instructions the Government gave the members of the grand jury,” prosecutors wrote. “The argument’s premise and conclusion are both wrong.”

Robert and Maureen McDonnell were charged last month in a 14-count indictment that alleges that they repeatedly asked wealthy Richmond businessman Jonnie R. Williams Sr. for loans and for gifts of money, clothes, golf fees and equipment, trips and private plane rides. In exchange, the McDonnells allegedly worked together to lend the prestige of the governor’s office to Williams’s struggling company.

The McDonnells have since pleaded not guilty, and a trial is scheduled for July 28.

Monday’s filings — the first time prosecutors had responded to the McDonnells’ assertions about their case — offered a preview of the legal battle that will ensue.

McDonnell and his defense attorneys have insisted that the governor did not abuse his office, noting that Williams and his company received no state grants, contracts or economic incentives. That might undercut the notion of a quid pro quo, which prosecutors acknowledged in their filings they would have to prove.

But prosecutors wrote they would not need to show “a specific this-for-that correlation between each particular thing of value given and each particular official action performed or contemplated,” but only that McDonnell took gifts so he would act on a sort-of “as needed” basis.

And whether McDonnell’s actions were “particularly substantial,” they wrote, was also irrelevant; they must show only that the actions were “official.”

Prosecutors also rebuffed a suggestion by defense attorneys that they sought to conceal a financial relationship between Williams and Maureen McDonnell’s former chief of staff, and that showed they did not understand the need to turn over to defense attorneys any evidence that might exonerate their clients.

The prosecutors wrote that they planned to provide all relevant evidence as part of the normal discovery process.

Rosalind S. Helderman contributed to this report.