Mitt Romney on Monday threw out new charges and innuendo against former House Speaker Newt Gingrich, in what may be the political equivalent of throwing spaghetti against the wall—seeing what sticks. We’ve examined the often bogus charges made by Gingrich allies (and the Obama campaign) about Romney’s tenure at Bain Capital. So let’s take a look at what is known about the issues raised by Romney.

The Romney campaign accompanied its attack with a new ad amplifying some of these claims, which we will also examine soon. But first here is a guide to the latest rhetoric.

“We could see an October surprise a day from Newt Gingrich. And so let’s see the records from the ethics investigation, let’s see what they show.”

Actually, the records of the ethics investigation into whether Gingrich used tax-deductible donations to finance a college course have long been available. There is 137-page report summarizing the findings and more than 1,000 additional pages. It was not Gingrich’s finest hour—and he once earned Four Pinocchios for mischaracterizing what happened. But Romney is wrong to suggest there is much more to learn about this episode.

“Let’s see who his clients were at the time he was lobbying Republican congressmen for Medicare Part D. Was he working or were his entities working with any health-care companies that could’ve benefited from that? That could represent not just evidence of lobbying but potentially wrongful activity of some kind.”

This is a pretty serious but completely unsubstantiated charge, with Romney coming close to suggesting criminal activity by Gingrich.

The former speaker has denied engaging in lobbying and in an interview last month with Glenn Beck he suggested he supported the bill both because it included conservative-leaning market principles (Medicare Advantage and health savings accounts) and because the structure of Medicare had not kept pace with the advances in drug therapy. By some accounts, Gingrich’s speech to Republican lawmakers before the vote was important in switching some votes. But a lengthy report in Politico says he had little impact on the development of the bill as it moved through Congress--which would be evidence of real lobbying on behalf of clients.

The non-profit group Citizens for Responsibility and Ethics in Washington (CREW) has called for a federal investigation into whether Gingrich failed to register as a lobbyist while advocating for the Medicare bill. “I’m allowed as a citizen to say I’d like to see this passed and that’s not lobbying,” Gingrich told CNN.

“He said in a debate, actually, that people who profited from the failed model of Freddie Mac and Fannie Mae ought to give back their money. Well, the speaker made $1.7 million in his enterprises from providing services to Freddie Mac. He ought to give it back.”

Romney has also called on Gingrich to release his contract with Freddie Mac, for which Gingrich earned $1.7 million, and mocked the idea that the mortgage giant had hired Gingrich as “an historian.”

The contract was actually with Gingrich’s former company, the Center for Health Transformation. According to Bloomberg News, the company turned the matter over to its lawyer, Stefan Passantino, also national counsel for the Gingrich campaign, who “said in an e-mail this month that he wouldn’t let the company release the document because, ‘The risks of any kind of confidentiality waiver, even if the company tried to limit it to one client or one document, are too great to be feasible.’”

But on ABC’s “Good Morning on Monday, Gingrich said he had asked the company to release it, saying: “I’m very comfortable with it being released.”

Gingrich’s “historian” comment came as part of one of the many GOP debates. “I have never done any lobbying, every contract that was written during the period when I was out of the office specifically said I would do no lobbying, and I offered advice,” he said. Then he added that “my advice as a historian” was that their business model of “making loans to people who have no credit history” was “insane.”

Gingrich has a doctorate in history, writing his dissertation on the Belgian Congo, but he loves to cite his “historian” credentials to opine on many subjects. Reporters have found no evidence that he made these comments to Freddie Mac.

Bloomberg News reported that Gingrich’s “primary contact inside the organization was Mitchell Delk, Freddie Mac’s chief lobbyist, and he was paid a self- renewing, monthly retainer of $25,000 to $30,000 between May 1999 until 2002, according to three people familiar with aspects of the business agreement.”

Indeed, Freddie Mac’s Web site includes a transcript of 2007 interview with Gingrich in which he praised government-sponsored enterprises such as Freddie Mac. I like the GSE model because it provides a more efficient, market-based alternative to taxpayer-funded government programs,” he said. “Certainly there is a lot of debate today about the housing GSEs, but I think it is telling that there is strong bipartisan support for maintaining the GSE model in housing.”

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