New this month Character mistake: When Kate pretends to be Abby, trying to trick Ari, he deduces that she's not upon seeing her gun in its holster, and doesn't pick up on the more blatantly obvious fact that her manner of dress doesn't match Ducky's description of Abby as a Goth.
Factual error: The season 5 episode "Designated Target" deals with the murder of a Navy admiral and the cab driver transporting him through Rock Creek Park in Washington, DC. Late in the episode, the investigators try to get a lead on another cab driver by tapping into the records from taxi meters. The problem is, DC cabs don't yet have meters. Congress banned them in 1933, but legislation passed this year now gives the DC government authority to install meters. And in fact, just days before this episode aired in Nov 2007, DC's mayor announced plans to switch from the zone system to meters by April 2008.