The case is Brown v. Education Merchants Assn, decided on July 27. You can understand why California tried to make these games illegal. Justice Alito's concurrence describes what these games are about:
In some of these games, the violence is astounding. Victims by the dozens are killed with every imaginable implement, including machine guns, shotguns, clubs, hammers, axes, swords, and chainsaws. Victims are dismembered, decapitated, disemboweled, set on fire, and chopped into little pieces. They cry out in agony and beg for mercy. Blood gushes, splatters, and pools. Severed body parts and gobs of human remains are graphically shown. In some games, points are awarded based, not only on the number of victims killed, but on the killing technique employed. It also appears that there is no antisocial theme too base for some in the video-game industry to exploit. There are games in which a player can take on the identity and reenact the killings carried out by the perpetrators of the murders at Columbine High School and Virginia Tech.
The objective of one game is to rape a mother and her daughters; in another, the goal is to rape Native American women. There is a game in which players engage in “ethnic cleansing” and can choose to gun down African-Americans, Latinos, or Jews. In still another game, players attempt to fire a rifle shot into the head of President Kennedy as his motorcade passes by the Texas School Book Depository.
OK, so we know the games are bad. But Justice Scalia, writing for the majority, notes there is no historic tradition to shield minors from violent literature and other forms of mass media. He notes that childrens' books, including the Grimm's Fairy Tales, are violent, as are high school reading lists. We put up with all sorts of offensive speech, from flag burning to racist speech, none of which can be regulated by the government. Years ago, we put up with offensive comic books and movies. As The Court majority notes, people cries wolf back then, but the "anything goes" mentality will always seem to govern these cases. Last year, the Supreme Court held that the government cannot outlaw videos showing people crushing animals to death. This time around, violent video games are equally protected.
In dissent, Justice Thomas takes an originalist approach to the First Amendment that no one else on the Court agrees with. Through exhaustive research, he argues that when the First Amendment was adopted in the Eighteenth Century, it was understood that parents were able to control what their minor children could see and hear. He writes:
The practices and beliefs of the founding generation establish that “the freedom of speech,” as originally understood, does not include a right to speak to minors (or a right of minors to access speech) without going through the minors’ parents or guardians.
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In my view, the “practices and beliefs held by the Founders” reveal another category of excluded speech: speech to minor children bypassing their parents. The historical evidence shows that the founding generation believed parents had absolute authority over their minor children and expected parents to use that authority to direct the proper development of their children. It would be absurd to suggest that such a society understood “the freedom of speech” to include a right to speak to minors (or a corresponding right of minors to access speech) without going through the minors’ parents. The founding generation would not have considered it an abridgment of “the freedom of speech” to support parental authority by restricting speech that bypasses minors’ parents.
Justice Thomas's scholarship on this issue is all very interesting, but no one else is buying this. A few years ago, he argued in Morse v. Fredericks, 551 U.S. 393 (2007), that the Supreme Court's seminal case in favor of high school students' First Amendment rights (Tinker v. Des Moines School District, 391 U.S. 503 (1969)) should be overruled because the original understanding of the First Amendment in the Eighteenth Century did not recognize that school children had any First Amendment rights at all. No one else on the Supreme Court joined in that analysis, either.