What would Jefferson have made of the grubby trial involving Virginia's former governor?

Out of America: Republican Bob McDonnell and his wife were the perfect political couple... until those corruption charges

Trial and error: Maureen and Bob McDonnell (centre) face a 14-count indictment (Getty)

Virginia still likes to call itself a commonwealth, a superior sort of place where the air is sweeter, the streams clearer and where politicians know always to promote and protect the "wealth" of all the people over their own. It was also home, of course, to the most revered of all America's leaders, George Washington and Thomas Jefferson.

This August, however, the genteel people of Richmond, the state capital, in their pearls and summer seersucker, are positively aquiver over the trial now under way in their midst of their former governor Bob McDonnell and his wife, Maureen, accused by the feds of enriching themselves illegally, fleecing the pockets of a local businessman who needed help getting traction for an anti-inflammatory dietary supplement he'd invented.

The grubbiness being alleged – we are talking $165,000 in gifts and cash – isn't meant to happen in Virginia. In Illinois, yes, where four of the last seven governors were imprisoned for corruption; or Louisiana, where Edwin Edwards, a former two-term governor, served eight years (and now, why not, is running for Congress).

With his cornflower eyes and impeccable hair, Mr McDonnell, a Republican, had seemed, well, perfect. He delivered his party's response to President Barack Obama's State of the Union address in 2010 and was talked about as a possible running mate for Mitt Romney in 2012. And he had the perfect marriage, of course. Or not. "I think these issues of life, family and marriage kind of define who we are as people," he noted in one interview.

No sooner had he left office in January, however, than he and his wife were indicted on 14 charges. If convicted, they could both face up to a decade in prison. It allegedly began with a $5,000 bottle of Louis XIII Cognac given to the couple, even before the governor's 2009 inauguration, by Johnnie Williams, whose company, Star Scientific, had come up with the supplement, an extract from tobacco called Anatabloc. But that was only the start.

Later came the day Mr Williams took Mrs McDonnell on a shopping spree to Manhattan, buying her Oscar de la Renta dresses and goodies from Bergdorf Goodman and Louis Vuitton, together worth $20,000. For the governor, there was the free use of Mr Williams' lavish holiday home and white Ferrari, and golf, at $400 a round. Oh, and a Rolex. A bigger deal for prosecutors, however, is the $100,000 in cash and loans allegedly received from Mr Williams.

At the time that Mr McDonnell was serving, there were no state laws against government servants accepting gifts of any size. The challenge for the prosecution at the trial, which is expected to last a month, is to prove that the largesse of Mr Williams was given, and received, on the clear understanding that the influence of the governor's office would be availed in return. That is influence-peddling. The prosecution says this is exactly what Mr McDonnell and his wife were up to and that it was a joint conspiracy. They regularly complained they were impoverished and in debt.

The trial is proving nothing if not excruciating for the McDonnell clan. There was the former chief of staff to Mrs McDonnell, Mary-Shea Sutherland, recalling last week how her boss would yell at her so loudly, that security agents would come rushing to see what was wrong. And she confirmed that, yes, she had told the FBI she considered her a "nut-job". And then there are the hundreds of texts sent by Mrs McDonnell to Mr Williams, including one on the day of a minor earthquake in 2011 that read: "I just felt the earth move and i wasn't having sex!!!!"

But the defence strategy that has really got Richmond eyebrows twitching is the contention that the perfect marriage the couple projected while Mr McDonnell was in office was a sham – that the governor, rather, was married to a woman who "hated him".

William Burck, on the legal team for the first lady – each have hired different sets of defence lawyers – contended that she had not only become totally estranged from her husband but that she had also fallen into an emotional sinkhole and had taken Mr Williams as her "favourite playmate", hinting at an affair. By that reasoning, husband and wife couldn't have conspired to tap Mr Williams's fortune because they were barely speaking to each other. The implication, moreover, is that his generosity had to do only with affection for Mrs McDonnell and nothing more.

Mr Williams, who took an immunity deal to testify, has not been helping to advance this narrative, however, saying that he had no clue that Mrs McDonnell had a crush on him until it came up at trial and making clear that, of course, he expected something back for his generosity. It was hardly in his interest to dole out cash to the first lady without the governor being aware. (That included one loan of $15,000 to help pay for their daughter's wedding.)

"He's the breadwinner in his house," Mr Williams said on the stand. "I'm not writing his wife cheques without him knowing about it." It was in this way, according to the prosecution, that a luncheon specifically to promote Anatabloc was hosted by both defendants in the governor's mansion in 2012. Similarly, Mr Williams testified that he had had direct conversations with the governor about help that his office might give him with marketing his pills, which were swiftly followed up by the governor switching the topic to his personal penury.

Before the trial is over, the former governor is expected to take the stand to testify in his own defence. That is a day when all normal social activity in Richmond will surely come to a halt. There is no predicting the verdicts but, prison or no prison, the reputations of the couple are already surely as wrecked as their marriage is purported to be. And, likewise, Mr McDonnell's political career – unless, perhaps, he moves to Louisiana.

Rupert Cornwell is away