On October 26, 1954, the Comics Magazine Association of America, Inc. formed the Comics Code Authority and the Comic Code to self-regulate the comic book industry. Since that time the Comic Code was updated and amended to allow for things like the depiction of narcotics or homosexuality, but the purpose remained the same. The code gradually lost support due to the growing trend in darker comics such as Frank Miller's "Dark Knight" comics and Alan Moore's "Watchmen" and "Swamp Thing" saga, which were exempt from the code due to their strong violence, adult language and sexual themes. No publishers use the code anymore. Marvel Comics dropped the CCA in favor of its own ratings system.
- http://www.comicartville.com/comicscode.htm Comic Code