RICHMOND, Va. (AP) — The prosecution's key witness will be back on the stand today when the corruption trial of former Virginia Gov. Bob McDonnell and his wife, Maureen, resumes at the federal courthouse in Richmond.

Jonnie Williams is testifying under immunity. Williams is the former CEO of dietary supplements maker Star Scientific Inc. The McDonnells are charged with accepting more than $165,000 in gifts and loans from Williams in exchange for helping promote his company's products.

Last week, Williams testified that he and the McDonnells had a business relationship and were not personal friends. Defense attorneys sought to contradict that claim by noting that Williams and Maureen McDonnell exchanged more than 1,200 text messages and phone calls in less than two years.

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