The character of Detective Robert Goren is based on Sherlock Holmes, but instead of relying upon physical evidence like Holmes, D'Onofrio's character focuses on psychology to identify the perpetrators, whom he often draws into confessing or yielding condemning evidence. The character of Nicole Wallace is a direct attempt to play on the part of Sherlock Holmes' female antagonist Irene Adler, also known as "The Woman." Wallace is employed as a 'Professor of Literature' during her first appearance, which could be a parallel to Holmes's nemesis Professor Moriarty.
At the end of the 4th season, Jamey Sheridan suffered Bell's palsy, a facial paralysis that affected one half of his face. In the 5th season his character, Captain James Deakins, carried an eye patch over his left eye to hide the sequels of the paralysis.
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." This is the only Law & Order series where the opening statement does not begin with the words "In the criminal justice system..."
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.