Indicating ignorance on a subject to be somehow legitimate because "I wasn't born yet."
As when confronted by Paul Begala, on HBO's Real Time With Bill Maher, with the fact that Ronald Reagan blamed his problems on Jimmy Carter for many years, Meghan McCain responded, "I wasn't born yet, so I wouldn't know."
To which Begala replied, "I wasn't born during the French Revolution but I know about it!"
I asked my friend Daniel, "Who's bigger, Michael Jackson or Elvis Presley?"
Daniel: "Who's Elvis Presley?"
Me: "The King of Rock and Roll? Hello? '50s, 60s, 70s?"
Daniel: "How should I know? I wasn't even born then!"
Me: "Dude. Are you seriously pulling a Meghan McCain?"