The US Supreme Court prepared to hear arguments on Tuesday on whether a California ban on the sale or rental of violent videogames to minors is unconstitutional.
The case stems from California's approval in 2005 of a law that would make retailers subject to fines of 1,000 dollars for selling or renting videogames labeled as violent to anyone under the age of 18.
Opponents of the law argue it restricts freedom of expression enshrined in the First Amendment of the US Constitution and is unnecessary because most videogames already contain ratings as to their age appropriateness.
The California law was overturned by a lower court in 2007 as infringing on free speech, and that ruling was upheld by a higher court in 2009.
California Governor Arnold Schwarzenegger appealed the case to the Supreme Court and the nine justices were to hear arguments on Tuesday in "Schwarzenegger v. Entertainment Merchants Association."
The law defines a violent videogame as one that depicts "killing, maiming, dismembering, or sexually assaulting an image of a human being," though it does not prevent a parent or guardian from purchasing the game for their child.
Supporters of the law point to medical and sociological studies they say establish a correlation between violent videogames and aggressive thoughts, antisocial behavior and desensitization to violence.
Nearly a dozen other US states have come out in support of the California law or attempted to pass similar legislation.
California state Senator Leland Yee, a child psychologist who co-sponsored the law, urged the Supreme Court to uphold the ban.
"I am hopeful that the Supreme Court will help give parents a valuable tool to protect children from the harmful effects of excessively violent, interactive video games," the Democrat from San Francisco said in a statement.
"Parents -- not retailers or game makers -- should be able to decide whether or not their children can play in a world of murder and violence that often degrades women and racial minorities," Yee said.
"The videogame industry should not be allowed to put their profit margins over the rights of parents and the well-being of children," Yee added.
Opponents of the California law argue that minors should have the same access to potentially violent videogames as they currently do to movies or books with similarly graphic content.
They say the law is not needed because the Entertainment Software Rating Board (ESRB) already rates thousands of games a year, providing parents with the ability to determine whether a game is appropriate for their child.
In a brief filed with the Supreme Court, the Electronic Frontier Foundation (EFF) and the Progress and Freedom Foundation urged the justices to protect the free speech rights of videogame creators and users.
The groups pointed to a research by the US Federal Trade Commission (FTC) which found that the videogame rating and labeling system is "not only widely recognized by parents but is also well enforced."
The FTC survey found that 89 percent of parents are involved in the purchase or rental of a videogame for their child and that 87 percent are aware of the ESRB videogame ratings system.
EFF attorney Lee Tien said videogames "are fully protected speech, and both the 'violence' and 'interactivity' feared by California's law are expressive aspects of books, plays, and movies -- not just videogames.
"The government can't regulate speech content, even to protect children, if there are reasonably effective private rating systems and parental control tools that don't interfere with our First Amendment rights," Tien said.
Another opponent of the law, the Entertainment Consumers Association, described Tuesday's hearing as "the single most important moment for gamers, and the pivotal issue for gaming, in the sector's history."
Explore further: Christian Bale to play Apple's Steve Jobs