Continuity mistake: When Portnow meets with Bishop at the church, in the first closeup of Bishop's crossword puzzle the word "MUD" is the second word across at the top, and at the center of the puzzle the 4-letter word "GEAR" is written in the 5-letter answer - with the fist space left empty. However, in the next closeup of the puzzle, now the word "ETA" is the second word at the top and "MUD" is the third, and the word "GEARS" has the "S" added, with the letter "G" started properly in the first space of the answer. (00:10:15)Super Grover
Factual error: When Yuri is narrating about selling weapons for the US government (this was around the scene when he sells M-16's by the kilo), he mentions Lieutenant Colonel Southern. However, when you see the him, he has Colonel rank, which is a silver eagle. The Lieutenant Colonel rank is a silver leaf, not an eagle.
Factual error: Halfway into the film, a scene shows Capote talking on a beige telephone. The receiver is a modular (plug in) type. Modular phones were not introduced until after 1966. The time frame for this movie is 1959 through 1963. All other scenes in this movie show the correct type of receiver (wired, not plug-in).