Kathryn Erbe's real life pregnancy was incorporated into the show's plot line by having her character be a surrogate mother, carrying her sister's child.
Uses a re-mixed version of the theme music from "Law & Order" (1990), but a different re-mix than "Law & Order: Special Victims Unit" (1999). The episodes produced for the USA Network use the mix first heard on "Law & Order - Trial By Jury."
Alexandra Eames once mentioned dating a man named "Terry", possibly a reference to Kathryn Erbe's real-life husband, Terry Kinney.
The following statement appears at the beginning of each episode: "In New York City's war on crime, the worst criminal offenders are pursued by the detectives of the Major Case Squad. These are their stories."
To add a vulnerability to Goren's seeming invincibility, a backstory was added in which his mother was diagnosed as a schizophrenic during his adolescence.
'Vincent D'Onofrio (I)''s contract is for seven consecutive years on the show.
Olivia d'Abo's fate as a recurring villain was once held in the balance by a phone-in poll. An overwhelming majority of fans voiced their desire for her to get away again.
The character of Detective Robert Goren is based on Sherlock Holmes.
The show's format was partially inspired by the NBC Columbo mystery movies staring Peter Falk. Both started out with the crime being seen from the criminals point of view and with them confident that they can get away with it. However, they then get outsmarted by a brilliant detective. The shows differ in that "Columbo" usually shows the full crime in the beginning while in "Law & Order: Criminal Intent" the viewer is only shown enough to be a few steps ahead of the detectives in knowing what happened. Goren and Columbo also have very different styles in analyzing the crime and the suspects.
Beginning season 5 (2005-2006) episodes' cast and opening credits alternate between Goran/Eames ('Vincent D'Onofrio (I)' and Kathryn Erbe) and Logan/Barek (Chris Noth and Annabella Sciorra). On season 6 Julianne Nicholson replaced Sciorra.