RICHMOND, Va. (AP) — Former Gov. Bob McDonnell’s attorneys are seeking documents from two federal agencies that they hope to use to attack the credibility of the government’s expected star witness in his public corruption case.

McDonnell and his wife, Maureen, are charged with accepting more than $165,000 in gifts and loans from the head of a dietary supplements company in exchange for helping promote his products. They’ve pleaded not guilty. Their trial is set for July 28.

Defense attorneys late Thursday filed papers asking a federal judge in Richmond to issue subpoenas for Food and Drug Administration and Securities and Exchange Commission files on Star Scientific Inc. and its former CEO, Jonnie Williams. Both agencies have investigated the company.

McDonnell’s attorneys say documents in those files will be essential to evaluating Williams’ testimony.