The film opened on 30 September 2005, which is Truman Capote's birthday.
Some of the prison guards in this movie are real correctional officers from Headingley Correctional Center & Correctional Service of Canada's Stony Mountain Institution
The James Baldwin novel referred to by Truman Capote in the opening party scene as a "problem novel" is "Another Country".
The boy known as Danny Burke in the movie was actually Bobby Rupp in Capote's novel In Cold Blood, while the girl called Laura Kinney in the film is actually Susan Kidwell. The names were probably changed for legal reasons.
In the movie The Big Lebowski (1998), the photo that the PI shows the Dude of Bunny Lebowski's farm is the photo of the real Clutter home, where the murder chronicled in Truman Capote's "In Cold Blood" took place. Two "Lebowski" actors went on to appear in Capote (2005): Philip Seymour Hoffman (Brandt in "Lebowski"), plays Truman Capote, and 'Mark Pellegrino', (Blond Treehorn Thug in "Lebowski"), plays Dick Hickock (one of the murderers of that farm's inhabitants).