Ratcheting up her offensive against the news media, Gov. Sarah Palin’s attorney threatened Saturday to sue mainstream news organizations if they publish “defamatory” stories relating to whether Palin is under federal investigation.

In an extraordinary four-page letter, Alaska-based attorney Thomas Van Flein warns of severe consequences should speculation that until now has largely been confined to blogs about whether Palin embezzled funds in the construction of a Wasilla, Alaska, sports arena find its way into print.

“This is to provide notice to Ms. Moore, and those who re-publish the defamation, such as Huffington Post, MSNBC, the New York Times and The Washington Post, that the Palins will not allow them to propagate defamatory material without answering to this in a court of law,” Van Flein warned, citing Alaska liberal blogger Shannyn Moore.

Keep in mind, neither the New York Times nor the Washington Post made any reference to the embezzlement rumors, but Palin’s lawyers apparently threatened the papers anyway, just in case editors were thinking about looking into the allegations.

I can’t speak to the veracity of the embezzlement accusations, though an FBI official said yesterday the governor is not a target of a public corruption investigation. That said, the threatening letter seems like an odd strategy for the governor’s attorney. For one thing, it’s awfully difficult to win a defamation case against a news outlet covering public officials.

For another, there’s no surer way to pique a reporter’s interest in allegations than demanding that major outlets ignore the issue.

Steve Benen

Follow Steve on Twitter @stevebenen. Steve Benen is a producer at MSNBC's The Rachel Maddow Show. He was the principal contributor to the Washington Monthly's Political Animal blog from August 2008 until January 2012.