The wheeling-and-dealing Richmond businessman at the center of the corruption case against former Virginia governor Robert F. McDonnell and his wife stepped into public view Wednesday with a pivotal assertion: For $65,000, he testified, Maureen McDonnell said she would help his company, with her husband’s blessing.

“She said to me, ‘I have a background in nutritional supplements, and I can be helpful to you with this project with your company,” Jonnie R. Williams Sr. testified, describing a private meeting with Maureen McDonnell in the governor’s mansion in May 2011. “ ‘The governor says it’s okay for me to help you, but I need you to help me with this financial situation.’ ”

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Williams provided riveting testimony for more than an hour during the third day of a trial that already has made a dramatic spectacle of the couple that occupied the Virginia governor’s mansion just seven months ago. Williams described how he lavished cash and high-end clothing on Maureen McDonnell, in particular, and how the first lady seemed to push the boundaries of his generosity.

Williams, who is scheduled to take the stand again Thursday, began to outline what had been his grand plan for advancing his company’s dietary supplements by using the “credibility” of the governor’s office and persuading the governor to spur state research of his wares.

“I know that [the governor] controls the medical schools, so I needed his help with the testing of this,” Williams testified.

Williams, 59, who has made no public statements in the 16 months since his relationship with the McDonnells burst into public view, arrived at the courthouse in mid-afternoon, reporters trailing him. He wore a dark business suit, and his hair was flecked with considerably more gray than in the few photos of him that have surfaced since the scandal broke.

In his testimony, Williams acknowledged that even when he promised to give Maureen McDonnell $65,000 — a $50,000 loan and $15,000 to help pay for her daughter’s wedding — he did so without a pledge that her husband would assist him.

The governor’s wife, Williams testified, had confided in him that she and her husband had discussed filing for bankruptcy because of mounting credit-card debt and troubled real estate investments. He said that he insisted on talking with the governor about the money but that even then, he did not try to convey that his generosity came with strings attached.

“He’s the breadwinner in the house, and I’m not writing his wife checks without him knowing about it,” Williams said. He said the governor thanked him for the gift.

Defense attorneys have asserted that Williams is a “master manipulator” who is testifying only because he received immunity from potential criminal charges. They have said that Maureen McDonnell had a “crush” on Williams and that she and her husband’s marital woes ran so deep that they barely spoke. The picture of marital discord runs counter to the allegation that the McDonnells conspired together to sell the governor’s office in exchange for gifts and cash — which is the essence of the 14 public corruption and related charges against them.

Williams — who spoke enthusiastically about his product, saying that he believes his pills cured his wife’s precancerous thyroid condition — also spoke of providing Virginia politicians with flights on his private jet in an effort to make his company, Star Scientific, successful.

A manicurist and a model are just two of the witnesses that may be called to testify in the federal corruption trial of former Va. governor Robert F. McDonnell and his wife, Maureen, which commenced on Monday. The Washington Post's Matt Zapotosky reports from Richmond on some of the standout witnesses on the list released by prosecutors and defense attorneys. (Ashleigh Joplin/The Washington Post)

“I think it’s become common practice if you’re a Virginia company. You want to make sure you have access to those people, and the airplane accomplishes that,” he said.

Williams described in detail an April 2011 New York shopping trip during which, he said, he, the first lady and her chief of staff went to high-end boutiques, including Bergdorf Goodman, Oscar de la Renta and Louis Vuitton.

By Williams’s account, Maureen McDonnell had intended to buy only two dresses but instead ran up a $20,000 tab, which he covered. She left with a full-length white leather coat, a pair of shoes, a raincoat and a dress.

“It went on for hours,” Williams said.

Williams’s appearance on the stand capped a day that included testimony about the range of gifts Williams gave to the governor, the first lady and their adult children.

One of the McDonnells’ twin 22-year-old sons, Robert “Bobby” Ryan McDonnell, testified that after Williams noticed his old, well-worn golf clubs during a round of golf in 2011, Williams called and said he was sending a present to the governor’s mansion. There, Bobby McDonnell found a new set of clubs in a bag with the University of Virginia logo on it, along with a pair of golf shoes.

Bobby McDonnell also testified about the now-notorious Rolex watch, which prosecutors allege Williams purchased in August 2011 at Maureen McDonnell’s request and which was engraved with the words “71st Governor of Virginia.” He said his mother gave the watch to his father for Christmas.

Bobby McDonnell said he assumed the watch was a fake because it “ticked” rather than “rolled.” He said his father — having already received a Seiko from Maureen McDonnell — thought simply, “Another watch?”

Throughout his testimony, Bobby McDonnell pushed back against the idea that his father was accepting inappropriate gifts from Williams or encouraging his sons to do so.

Bobby McDonnell said that his father thought the clubs were “excessive” but that he kept them anyway. He also said the governor persuaded him not to accept an internship Williams offered him.

The manager of an exclusive golf course outside of Richmond, where dues are $11,000 annually, testified that McDonnell and his sons played repeatedly on Williams’s tab in 2011 and 2012, each time racking up hundreds of dollars in greens and caddy fees and food and pro shop purchases. Only once did Williams golf with the governor; sometimes, McDonnell’s sons played without either their father or Williams, according to testimony.

Jerri Fulkerson, Williams’s onetime personal assistant, testified about private plane and vacation arrangements for the McDonnell family.

There was a family vacation for the McDonnells to Williams’s Smith Mountain Lake vacation home in July 2011. (Fulkerson testified that a Star Scientific employee drove Williams’s Ferrari there for the governor’s use and then got a ride in another vehicle back to Richmond.) There was a vacation for the governor and his wife at the exclusive Chatham Bars Inn on Cape Cod during Labor Day weekend 2012, including dinners, golf games, a day of yachting and spa treatments.

Fulkerson testified that during that same weekend, she made arrangements for the McDonnells’ 25-year-old daughter, Rachel, to fly to Florida with a friend. The two stayed at Williams’s condo, and Fulkerson arranged flights, passes to the Ritz-Carlton Beach Club and a yacht outing.

Fulkerson acknowledged that Williams made his plane available to a number of other politicians — including Jerry Kilgore and Ken Cuccinelli, during their respective tenures as state attorney general, and presidential hopeful Mitt Romney — but she said the McDonnells were an unusual case.

In one instance, Maureen McDonnell’s chief of staff asked for Williams’s private jet to fly three of the governor’s children to the Homestead resort in western Virginia for an annual political event for the governor, according to an e-mail Fulkerson read aloud. The chief of staff indicated in the e-mail that the plane should pick up the governor’s twin sons in Richmond, fly to Virginia Beach to pick up his eldest daughter and then fly on to the resort, Fulkerson said.

Ultimately, the eldest daughter flew out of Richmond with her brothers. But Fulkerson noted the chief of staff’s odd request.

“Can you recall any other time when a politician asked for the use of Mr. Williams’s plane to transport their children over a space of a one-and-a-half-hour drive?” federal prosecutor David Harbach asked Fulkerson.

“No,” she responded.

“Do you recall a time any other politician asked for the use of Mr. Williams’s plane to fly their children at all?” he continued.

“No,” she answered.

Justin Jouvenal and Rachel Weiner contributed to this report.