The Electronic Frontier Foundation, a civil liberties advocacy group, says that requiring video games to carry a warning that they may cause violent behavior in players may harm freedom of speech. The EFF’s warning is in response to a bill, the “Violence in Video Games Labeling Act” (HR 4204), introduced this week by Reps. Joe Baca (D-CA) and Frank Wolf (R-VA), which seeks to make the inclusion of these “cigarette-style” warnings a requirement for nearly all video games.

“Rep. Baca tries to cloak his anti-speech bill by the inapt comparison for tobacco warning labels in the press release announcing the bill,” writes Parker Higgins, an EFF activist. “But while there is a wealth of proof that cigarettes are dangerous, studies simply haven’t conclusively demonstrated a causal link between video games and aggressive behavior.”

Under the Baca/Wolf bill, the packaging of video games rated “E” (Everyone), “Everyone 10+” (Everyone 10 and older), “T” (Teen), “M” (Mature), or “A” (Adult) by the Entertainment Software Ratings Board (ESRB) must include a label that reads, “WARNING: Exposure to violent video games has been linked to aggressive behavior.” Only games rated “EC” (Early Childhood) would be exempted from the rule. However, as Higgins points out, there is no conclusive evidence that video games cause players to act violently (pdf).

(It should be noted that the ESRB voluntarily labels games with these ratings. They are not required by law, just as the inclusion of movie ratings by the MPAA and “Parental Advisory” labels on albums by the RIAA are not legally mandated.)

Not only is HR 4204 potentially on the wrong side of science, it appears to be on the wrong side of the law. A 2010 Supreme Court ruling (pdf) declared that “video games qualify for First Amendment protection,” just as books, plays, and movies do. Because of the precedent set by this Court decision, as well as other lower-profile cases, “video games are legally protected speech, and can’t be singled out for special restrictions,” says Higgins. Any attempts by state or federal governments to impose such restrictions will likely be shot down in court.

Of course, it is still possible that video games actually do cause violent outbursts, or at least desensitize frequent players to violence. A study published last year by the Journal of Experimental Social Psychology showed that young adults who played excessively violent video games did display noticeable cognitive differences from those who played non-violent games.

“A single exposure to a violent video game won’t turn someone into a mass murderer,” Dr. Bartholow of the University of Missouri told CBS News. “But if someone has repeatedly exposed themselves, these kinds of effects in the short term can turn into long-term changes.”

Regardless, the evidence on this matter is far from conclusive, which means the Baca/Wolf proposal is, at the very best, premature. To fight back against this bill, the EFF has created an “Action Alert” that easily allows concerned citizens to contact their representatives in Congress.