To prepare for her role as Elle, Reese Witherspoon spent two weeks studying the behavior of sorority girls, as she did not wish to portray a stereotypical airhead sorority image. She states on the DVD commentary that they were all very kind and polite, and she enjoyed her time with them. She also observed women shopping from the café at Neiman Marcus, and attended law school for a day.
During the opening credits, a group of (mostly) guys is seen wrestling on a lawn in front of a fraternity house. These folks are actual Caltech students, and were a last-second addition to this scene: they showed up on the set (the row of fraternity and sorority houses featured are administrative buildings on the edge of Caltech's campus) unannounced and were invited to join in the filming.
The Broadway musical based on the movie opened at the Palace Theater on April 29, 2007 and has ran for 595 performances closing on October 19, 2008. The musical was written by Laurence O'Keefe, with Laura Bell Bundy starring as Elle Woods. Laura Bell Bundy was nominated for the 2007 Tony Award for Actress in a Musical.
At the party, Enid Wexler announces that the term 'semester' refers to semen and should be changed to 'ovester' (as a reference to ova). In reality the word semester comes from Latin and means "a six month period".
The trivia items below may give away important plot points.
Neither the confrontation with Warner outside the courtroom nor the final graduation scene was a part of the original script. When the movie was tested, audiences were so wrapped up in Elle's story they were disappointed that she never got her revenge on Warner, and they also wanted to know what happened to her in the end (did she become a lawyer after all?). The two scenes had to be shot in England, because Reese Witherspoon and Matthew Davis were both filming there (she was filming The Importance of Being Earnest (2002), while he was filming another project) at the time. Great Hall of Dulwich College in London played Harvard Law School. During the graduation scene, only Witherspoon and Davis are actually present. Shots of Jennifer Coolidge, Selma Blair, Luke Wilson and other supporting cast members were filmed in LA and the whole thing was edited together later. Both Witherspoon and Wilson are wearing wigs: she had cut her hair short since finishing filming and she is much paler than in court; he had shaved his head for The Royal Tenenbaums (2001) and got a much deeper tan. However, since two years have elapsed in the film, this is acceptable.
Producers originally wanted to set the film at The University of Chicago. School administrators declined, however, because of a scene toward the end of the movie where a professor places his hand on Elle's leg. Filmmakers subsequently decided to have the story take place at Harvard University.