This Film Is Not Yet Rated/Ashley Bergman
Founded by the major Hollywood studios to head off the threat of government censorship and run for most of its history by Jack Valenti, a former staff member in Lyndon B. Johnson’s White House, the association often seems more arbitrary and less transparent in its workings than any federal agency this side of the C.I.A.
-A.O. Scott, New York Times.
The most interesting thing about that statement up there is that the ratings system was designed to prevent censorship when through the film "This Film Is Not Yet Rated", the point seems to be that the ratings system, in a way, censors. Mostly the film looked at how films rated NC-17 were doomed to flail financially and die an obscure death. Then it compared nearly identical scenes from R-rated movies to scenes from NC-17-rated films, the only major difference being gender (e.g. pubic hair of one woman in one film leading to an NC-17 rating while male pubic hair in another leads to an R rating, or female masturbation in "But I'm a Cheerleader" leading to an NC-17 rating while Jason Biggs masturbating with a pie leads to an R rating) or heterosexual vs homosexual depiction, with the latter earning an NC-17 rating far more often. Of course it is dangerous to simply believe based on the scenes shown that the only reason for the differentiations in ratings are due to gender or sexual orientation as Kirby Dick chose which scenes to show and, unless we've seen the films ourselves, we have no way of knowing whether or not the NC-17 films are truly deserving of the rating for other scenes.
But regardless, the MPAA doesn't help itself much with its insistence on secrecy and arbitrary rating system. Kirby Dick focuses a lot on why can't he know the identities of the raters with Joan Graves' main argument being that it would put too much pressure on the raters. This is clearly a weak argument as many, many political figures are in the spotlight and have to deal with much more pressure (think of the president, for example). Furthermore, one incredibly annoying moment in the film has an MPAA lawyer telling Kirby Dick he cannot, during the appeal, mention other films and their ratings when defending his own. The movie makes the point that if the judicial system uses precendents, why shouldn't the rating system? All in all the rating system seems flawed in ways that are detrimental to many filmmakers and is in need of some refurbishment.