[tremon]

The editorial staff should have been checking too

In what world should the editor double check third-party quotes in an article submitted by a journalist? Do you think the Washington Post phones the White House every time an article quotes the president (ok, bad example, pretend I asked this question about a serious paper in a healthy democracy)?

There's also such a thing as journalistic confidentiality -- the editor may not even know the identity of the quoted source. That doesn't apply to this specific case but your claim was generic, and I think there's a serious misapprehension here if you think it's the editor's job to verify citations in journalists' writings.