From politics to prison? The dramatic fall of John Edwards

He strides into the wood-panelled courtroom looking much as he did four years ago when he was a candidate for the Democratic nomination for president. Sharp in a suit, his hair as flawless as it ever was, ex-Senator John Edwards stops to greet a friend in the public benches before settling in his leather swivel chair at a table near the front. Then the judge and jury come in and we are reminded again: this is not the man we once thought we knew.

That is an understatement. A recent CBS News poll found that Mr Edwards' approval rating in America today is only 3 per cent. Over the months and years since he quit the 2008 primaries, the country has learned by slow drip of the car-crash that was his private life. Now, in Greensboro, North Carolina, we are here to dredge the ghastly details: the girlfriend, the out-of-wedlock baby, the spurned wife now deceased.

But being a lousy person is not a crime and he is not on trial for that. Rather, over 14 days of prosecution testimony that ended on Friday, the government argued that the man who once dreamed of being president violated election-financing laws by tapping two wealthy donors – Bunny Mellon, a banking heiress who is now 101-years old, and Fred Baron, his former finance chairman – for nearly $1m (£622,100) to cover his adulterous tracks and protect his candidacy and hopes for political resurrection. Under federal law, $4,600 is the most an individual can give a candidate for president.

The defence for Mr Edwards, who was a successful trial lawyer until he was elected to the US Senate in 1998, must begin its case this morning. Experts differ on how steep a hill the defence team must climb to ensure not-guilty verdicts for all of the six charges filed against him.

If his defence team fails, he could face up to 30 years behind bars. The battle over the likeability of Mr Edwards has surely already been decided, which is ironic if you recall that his success as a politician – a US Senator who was John Kerry's running mate in 2004 and then a primary candidate in 2008 – rested on his particular populist appeal, not to mention the hair. Still, on this one afternoon near the end of the prosecution case, you might have felt a twinge of sympathy for him.

It happened when Jennifer Palmieri, now a White House deputy communications director, but who in 2008 was a consultant for the Edwards campaign, was brought to the stand. Of interest to the prosecution: her very close relationship with Elizabeth Edwards, who was first in line to suffer when the truth of her husband's liaison with his campaign videographer, Rielle Hunter, came to light. The prosecution wanted to hear more of how she found out about the mistress, the steps that were taken to contain her and, much later, of Mr Edwards' paternity of the child.

But it was under cross-examination by the defence that Ms Palmieri was questioned about Ms Edwards' death from breast cancer in December 2010. Ms Palmieri was at her side and so, the court learned, was Mr Edwards, even though they had long been separated.

Ms Edwards had begged Ms Palmieri that he should be there. "Her concern was that when she died there would be a man around who had loved her," Ms Palmieri testified before breaking down. There had been other wrenching moments during the case for the prosecution; for example, when a former campaign aide recalled a distraught Ms Edwards collapsing on the cement of an aircraft hangar after learning of her husband's infidelity and then ripping off her shirt and bra to reveal her surgery-scarred breasts and crying: "You don't see me anymore."

If there was a moment when the jury could see the defendant only as a cad then this was it.

As the court heard of the deathbed request, we could not access the mind of the defendant but those of us close enough could see the strain on his face, his left hand cupped over his brow, the pinching of moisture from his eyes.

"I think that was one of the most powerful moments we have seen on the stand in this trial," said Hampton Dellinger, a former State Deputy Attorney General, who has observed the trial since the start. It was also a moment that was almost redemptive. "She made clear that she wanted Mr Edwards by her side despite everything he had put her through."

The prosecution, Mr Dellinger explained, faced a challenge from the start defining the significance of the nearly $1m, some of which was spent keeping Ms Hunter happy and away from the media. Mr Baron had her flown on a private jet to the West Coast and put her up in a luxury hotel. Some of the cash was channelled to Andrew Young, a top aide to Mr Edwards who agreed to pretend he was the father of Ms Hunter's child before the truth emerged. On the stand, Mr Young admitted that a large part of the money went to building a dream house for himself and his wife.

For charges to stick, the prosecution must show that money was accepted specifically for the purpose of the campaign – to stop a Rielle Hunter-induced meltdown – and that Mr Edwards knowingly sought it for that reason. "They have to demonstrate that he committed a knowing and wilful violation and that's a high standard. I still think whether the government answered that question is an open question," Mr Dellinger said at the end of last week.

"Things have been a little choppy for sure for the government," Kieran Shanahan, a Greensboro lawyer who has also monitored the trial, said. "They have done a pretty good job of demonstrating that Edwards had knowledge of the expenses of Fred Baron but I still think there are some missing gaps of law."

What the defence has not done is to try to pretend their client is an angel. That Mr Edwards repeatedly lied to his wife, as well as to the US public – particularly in an interview he gave to ABC News in August 2008, when he denied paternity – is plain. Abbe Lowell, his lead lawyer, told the jury as much last week. But Mr Lowell said there was "not one ounce of evidence" that Mr Edwards broke the law when he used the donations to hide his mistress.

It is uncertain if Mr Lowell intends to put Mr Edwards on the stand or, indeed, Ms Rielle, who has not been seen in the courtroom. If he calls either, it will be standing room only in Greensboro.