A fake journalist, a former shill for the Texas GOP, was issued a White House press clearance irecord time (5 days, according to one report). He would be called upon at presidential press conferencs, and Scott McClellan's briefings also, whereupon he would lob some diversionary questions to extricate the briefer from his predicament. This guy was called Gannon, but his real name, it turns out, is Guckert.
Read about it, and his alleged connections to the Valerie Plame case, on Yahoo.
Why did this even happen? Normally such an imposter would have been found out by his colleagues in a matter of minutes. Because, veteran report Dave Lindorff says, they are most of them incompetent anyway (The Perfect Plant - He Fit Right In).