It is not a crime to have an affair while your wife is dying of cancer, father a child with your mistress, and persistently deny both the affair and the child until forced to come clean when the guy who pretended to be the father finally admits the ruse. It is not even a crime to have such an affair while you are running for president. What is a crime, say federal prosecutors, is using your rich friends' money to conceal the affair by paying for your mistress's medical treatment, travel, and housing. According to an indictment announced on Friday, John Edwards violated federal campaign finance laws by soliciting nearly $1 million from two supporters of his campaign, Rachel Mellon and Fred Baron, to cover the cost of keeping Rielle Hunter and her baby out of sight. The indictment says "EDWARDS knew that public revelation of the affair and pregnancy would destroy his candidacy by, among other things, undermining EDWARDS' presentation of himself as a family man and by forcing his campaign to divert personnel and resources away from other campaign activities." Since revealing the affair would have hurt Edwards' campaign by destroying a carefully constructed facade of domestic bliss, the government says, that money was something of value "given to influence a federal election," which means Mellon (who gave $725,000) and Baron (who gave $200,000) far exceeded the individual campaign contribution limit of $2,300. Hence the various felony charges, involving conspiracy, illegal payments, and false statements, that together threaten the former North Carolina senator and Democratic vice presidential nominee with up to 30 years in prison and $1.5 million in fines.

Edwards says, in effect, "I may be a lying bastard, but I'm no felon." He argues that he sought to hide his affair from his wife rather than voters, for personal rather than political reasons. The Justice Department says the contribution limit "applies to anything of value provided for the purpose of influencing a federal election," including "payments for personal expenses of a candidate unless those payments would have been made irrespective of his/her candidacy." Suppose that Mellon bought John Edwards a $2,400 haircut. That would have been fine if she did it out of personal affection and if it is the sort of thing she would have done regardless of Edwards' political plans. But if she was thinking how important it is for a presidential candidate to be perfectly coiffed, according to the Justice Department, accepting her payment would be a crime. Edwards' guilt hinges on what Mellon (who is over 100) and Baron (who is dead) were thinking when they wrote their checks and on counterfactual speculation about whether they would have been so generous had Edwards not been running for president. Putting aside the question of whether there should be limits on campaign contributions, this theory seems pretty hard to prove beyond a reasonable doubt—except that a jury is apt to hold Edwards' contemptible personal behavior against him.

Edwards has lined up a former chairman of the Federal Election Commission, Scott E. Thomas, who says the indictment is based on a "novel and misguided theory." Rick Hasen, an expert on election law at U.C.-Irvine, says the theory is "plausible" but "is not going to be an easy case for the government to make." While both Common Cause and the Campaign Legal Center welcome the prosecution, Melanie Sloan of the Center for Responsibility and Ethics deems it "a silly case," saying, "John Edwards is horrible, but it doesn't mean they should be prosecuting him criminally."

Jeff Taylor notes that Bill Clinton and Arnold Schwarzenegger "used public dollars (via public employees and facilities they controlled) to hide their extramarital affairs and protect their 'presentations,'" which "has to be a greater affront to civic order" than relying on the help of rich friends. Taylor also points out that Edwards' phoney-baloney Center on Poverty, Work, and Opportunity at the University of North Carolina in Chapel Hill apparently was perfectly legal, even though it used millions of dollars in unrestricted and undisclosed donations to keep his political prospects alive after the 2004 election.

The indictment is here. ABC News has a helpful "scandal timeline" here.