Query: Which group was created after a Senate hearing on comic books content?
Context: The popularity of superhero comic books declined following World War II, while comic book sales continued to increase as other genres proliferated, such as romance, westerns, crime, horror, and humour. Following a sales peak in the early 1950s, the content of comic books (particularly crime and horror) was subjected to scrutiny from parent groups and government agencies, which culminated in Senate hearings that led to the establishment of the Comics Code Authority self-censoring body. The Code has been blamed for stunting the growth of American comics and maintaining its low status in American society for much of the remainder of the century.