I recently came across a statement from Mary Mapes concerning her well-deserved firing (hat tip: Little Green Footballs). I don't have the time to fisk the whole thing, and even if I had the time I doubt there is enough Zofran in the world to keep me on balance while I do it. But I would like to highlight one part of her incredibly self-serving rant, with my emphasis added:

Much has been made about the fact that these documents are photocopies and therefore cannot be trusted, but decades of investigative reporting have relied on just such copies of memos, documents and notes. In vetting these documents, we did not have ink to analyze, original signatures to compare, or paper to date. We did have context and corroboration and believed, as many journalists have before and after our story, that authenticity is not limited to original documents. Photocopies are often a basis for verified stories.

Mary, Mary, Mary...I think you've been reading too much Corey Pein. Exposing the documents as fake didn't rely on ink analysis, or looking at original signatures, or dating the paper on which the thing was printed. What made it laughably easy (and exposed your whole little effort as extremely childish) was the simple fact that in the space of five minutes, both Charles Johnson of Little Green Footballs and Joseph Newcomer were able to duplicate EXACTLY the memos in question, using only Microsoft Word with default settings. That's what made it such an amateurish forgery, and that's why you got caught.

Using Mapes' logic, the picture below should be accepted as a true copy of the Mona Lisa, mainly because you don't have ink to analyze, signatures to compare, or paper to date...but you have context and corroboration with me telling you it's a copy:

Obviously that is a fake, and a rather glaring one. If it was a photocopy you wouldn't need to look at the ink, or the signature, or the paper. You can tell just by looking at it. So it was with the memos.

Now, Mapes is correct in one thing: photocopies are indeed often used as a basis for stories. But she has a rather casual, rather glaring skip in her logic chain, to wit: the problem with the memos wasn't that they were photocopies, but that they were so spectacularly fake that the fact that they were photocopies was rendered immediately irrelevant. These memos receive no credibility simply by virtue of them being photocopies, or more precisely the fact that other photocopies have been used in other stories.

Further, as the story came out (and the CBS report made clear) the context and corroboration Mapes relied on was itself dependent on CBS staff telling those people the documents were real. That's not even that fine of a line to get tripped over, and that Mapes doesn't even acknowledge it speaks volumes. Her entire diatribe amounts to reiterating that the memos were "fake but accurate." Well, if that's the standard she wants to use to pursue a story, that's her choice.
But she ought not be surprised, nor insult our intelligence us with faux-outrage, when her credibility takes a well deserved hit as a result.