Was That Really Osama on Al Jazeera?

How the CIA can verify that the voice was his.

CIA analysts reported today that an audiotape broadcast on Al Jazeera this weekend—purported to be a voice recording by Osama Bin Laden—”likely” belonged to the al-Qaida leader. In March, Slate’s Brendan Koerner explained how intelligence officers figure out whether a voice on tape really belongs to Bin Laden, Saddam Hussein, or whoever else. The key: creating a “digital model” of the voice in question, “using archived snippets from past speeches.”