The outcome of the John Edwards trial is a sorry but fitting conclusion to a criminal case that should never have been brought. From the start, the prosecution of the former Democratic presidential candidate for alleged violations of campaign finance law reeked of moralistic vindictiveness. Edwards' political career had long since been destroyed. He had been disgraced and humiliated and may well have been the most despised man in the country. But for some, that was not enough.

Yes, Edwards' conduct was appalling; the betrayal of his cancer-stricken wife, the abuse of close friends, his hypocrisy, his unbounded ambition and vanity. These are not crimes. No one disputes that he accepted $1m from two wealthy supporters to conceal his adulterous affair. The issue was whether he did so to deceive his wife and preserve his family, or to further his 2008 campaign for the White House. As it happens, the Federal Election Commission decided Edwards had not broken the law. But that fact was kept from the jury. Meanwhile, thanks to the US Supreme Court's Citizens United ruling of 2010, opening the floodgates to unlimited individual contributions through so-called Super Pacs, the law has been transformed. Edwards was being tried for breaching rules that are effectively obsolete.

The criminal indictment of Edwards was driven by a North Carolina federal prosecutor with an eye on Congress, who may have calculated that the scalp of his state's most infamous Democrat could only boost his chances. If so, former US attorney George Holding was correct. Last month he won his Republican primary. The trial he secured, alas, was a waste of time and money.