The law, which was set to go into effect on July 27, would have fined retailers $500 for each game they sold to children under 17 that depicted violence against law-enforcement officials.
In issuing a preliminary injunction that blocks the law on Thursday, U.S. District Judge Robert Lasnik said the law was both overly broad and too narrowly targeted.
He said the games contained complex plot lines, original scores and detailed artwork and deserved the same free speech protection as other types of media. Banning the games, he said, would raise broader free-speech concerns.
"The act appears to sweep too broadly in that it would restrict access to games which mirror mainstream movies or reflect heroic struggles against corrupt regimes, such as 'Minority Report: Everybody Runs.'"
However, Lasnik also said that the law was "arbitrary," because it narrowly targeted violence against law-enforcement officials only.
"The state has not made any attempt to regulate the total amount of violence to which minors are exposed nor has it attempted to regulate all of the graphic violence depicted in video games, such as the murder and decapitation of women in 'Grand Theft Auto: Vice City,'" Lasnik said.
The law, which had been touted as a victory for parents seeking to control the amount of violence their children see while playing games, passed both houses of the Washington legislature earlier this year and was signed into law in May. In June, the Interactive Digital Software Association (IDSA) challenged the law on free-speech grounds.
The association applauded the preliminary injunction, saying it was in line with other court rulings on the matter. "U.S. District Judge Robert Lasnik affirmed that games are protected speech deserving similar protection afforded to literature, music, movies and other forms of creative expression," IDSA President Douglas Lowenstein said in a statement.
A spokesperson for Rep. Mary Lou Dickerson, D-Seattle, who sponsored the bill, did not immediately return a request for comment.
The law is believed to be the first of its kind at the state level. Last month, a federal appellate panela local ordinance that would have banned the sale or rental of graphically violent video games to youths in St. Louis County, Mo., saying it violates free-speech rights.