Newt Gingrich's SuperPac has posted a harsh new ad, accusing Mitt Romney of benefiting from Medicare fraud at a company called Damon back in the 1990s. Bain owned 8% of Damon. Damon's bad practices began before Bain's investment in the firm. In fact, according to Romney's biography, the first subpoenas arrived in the same month that Bain made its investment.
Nobody has ever suggested that Romney had any knowledge of the wrongdoing, much less any culpability, not even Romney's opponent in the 2002 Massachusetts governor's race, who first brought the matter to light a decade ago.
Indeed, if Romney followed the Newt Gingrich theory of evidence, as propounded in the South Carolina debate, he could answer: "How dare you ask about Damon! The matter has been discussed before and to discuss it again is close to despicable." Better, though, to rebut the charge than to complain about it.