In later interviews, Sylvester Stallone said he felt the film was supposed to be a comedy/action film, and demanded re-writes to make it even more comedic. The director and screenwriter, however, had intended a darker, more satirical approach, which led to many difficulties behind the scenes.
Director Danny Cannon was so disheartened over his constant creative disputes with Sylvester Stallone that he swore he would never again work with another "self-absorbed actor" (which was his own opinion of Stallone). He also claimed that the final version was completely different from the script due to the changes Stallone demanded.
The moment where Dredd takes off his helmet caused a lot of controversy. Judge Dredd would never remove his helmet in the comics. He took it off only once, but his disfigured face was covered with a censor bar.
The scene in which Fergie mocks Dredd was improvised, and it turned out to be so funny to see Rob Schneider making fun of Sylvester Stallone that it was kept in the movie.
In the Dredd comics, tradition dictates that Dredd does not take off his helmet, thus his face has mostly only fleetingly appeared in full, but the producers obviously would not allow an expensive performer, such as Sylvester Stallone, to never show his face clearly.