Try this, Deb — http://laws.findlaw.com/us/443/111.html
That is where Proxmire was sued for using his “Golden Fleece Award” where he maligned a Private Individual and group outside of his legally permitted venue of the Senate Floor.
Again...I HOPE YOU'RE RIGHT!
2. The Speech or Debate Clause does not protect transmittal of information by individual Members of Congress by press releases and newsletters. Pp. 123-133.
(a) There is nothing in the history of the Clause or its language suggesting any intent to create an absolute privilege from liability or suit for defamatory statements made outside the legislative Chambers; precedents support the conclusion that a Member may be held liable for republishing defamatory statements originally made in the Chamber.
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(c) The newsletters and press release were not privileged as part of the "informing function" of Members of Congress to tell the public about their activities. Individual Members' transmittal of information about their activities by press releases and newsletters is not part of the legislative function or the deliberations that make up the legislative process; in contrast to voting and preparing committee reports, which are part of Congress' function to inform itself, newsletters and press releases are primarily means of informing those outside the legislative forum and represent the views and will of a single Member. Doe v. McMillan, supra, distinguished. Pp: 132-133. 3. Petitioner is not a "public figure" so as to make the "actual malice" standard of proof of New York Times Co. v. Sullivan, 376 U.S. 254 , applicable. Neither the fact that local newspapers reported the federal grants to petitioner for his research nor the fact that he had access to the news media as shown by reports of his response to the announcement of the Golden Fleece Award, demonstrates that he was a public figure prior to the controversy engendered by that award. His access, such as it was, came after the alleged libel and was limited to responding to the announcement of the award. Those charged with alleged defamation cannot, by their own conduct, create their own defense by making [443 U.S. 111, 113] the claimant a public figure. Nor is the concern about public expenditures sufficient to make petitioner a public figure, petitioner at no time having assumed any role of public prominence in the broad question of such concern. Pp. 133-136. Pp. 127-130.
I doubt these Marines would be considered public figures, so the "acutal malice" standard would not apply in this case.