According to an interview with Jim Carrey, he says that the gag of Fletcher chasing his son as "The Claw" was something Carrey's father did to him and his siblings.
When Fletcher beats himself up in the restroom, no sound effects were used; those are really the sounds of Jim Carrey's head slamming into the urinal, floor, and walls.
Jim Carrey declined the role of Dr. Evil in Austin Powers: International Man of Mystery (1997) so he could be committed to this film, and also to take a break away from having to lose his hair, put on make-up, and wear eye-contacts for a role.
When Fletcher is having the pen war in his office, he comes up from behind the desk with the word Blue written all over his face. On his left jaw, "B.B. King" is written amongst all the blues.
Christopher Darden: As Fletcher Reede (Jim Carrey) is leaving the court building at the beginning of the film, he is asked "Hey Fletcher! How did it go in there?" by the real-life Chris Darden, the lawyer that prosecuted O.J. Simpson. Fletcher replies "Just another victory for the wrongfully accused!", to which Darden comments "Yeah right!" - which is a cynical play on O.J. Simpson being "wrongfully accused" for the murder of his ex-wife Nicole Brown Simpson.
Randall 'Tex' Cobb: The actor, who played "Gruff Man" in Ace Ventura: Pet Detective (1994), is seen at the beginning of the film, going into the court building and asking if Fletcher wants his coat back.