Chapter 22 - S2-E9
Factual error: Adam leaked the second photo after knowing that Remy could influence the Colombia's judge decision on the death penalty of his fiancée's father. However, the death penalty is unconstitutional in Colombia, so that decision wouldn't even be on the table.
Chapter 24 - S2-E11
Other mistake: In the end credits, "Frank Underwood" is misspelled as "Frank Undwerwood."
Chapter 25 - S2-E12
Continuity mistake: In the previous episode, Doug Stamper breaks his Blackberry after deleting Rachel and orders a new phone right away. Gavin Orsay (the technical guy) sees on his computer that there was a last message on September 30th 2014 at 9:22:22 and a lost of signal at 9:22:39. In this episode he uses the new Blackberry as he is receiving a text message from Rachel Posner: "It's done" on Saturday September 4th 2014 at 8:09, 26 days earlier than he destroyed his old phone. Bonus: September 4th 2014 wasn't even on a Saturday but a Thursday. (00:24:30 - 00:37:45)
Chapter 26 - S2-E13
Character mistake: Typing letter to the President on old typewriter, Frank thinks "stared at desk" but types "started at desk." (00:24:00)
