“There is no consensus among social scientists about the effect of viewing violent pictures.”

Robert M. Schwartz is a partner in the O’Melveny & Myers law firm in Los Angeles, and has represented filmmakers, studios and distributors in lawsuits claiming that motion pictures contributed to criminal conduct.

When an act of mass murder occurs, the entertainment industry is invariably put on a shortlist of potential culprits. Critics assert that movies and television programs depict violence excessively and insensitively, market the content inappropriately and are responsible for creating a culture of violence and inhumanity.

Some also ask whether the entertainment industry is culpable not only morally, but legally. The answer should be no. Usually, the courts or the legislative system are invoked in an attempt to impose liability on filmmakers and distributors for allegedly inspiring the perpetrators to commit their heinous acts.

Alternatively, the legal system is asked to regulate the content — or at least the advertising — of motion pictures, television programs, videogames and other expressive works. Having represented industry members in both areas, it’s my opinion that our resources would be better spent looking elsewhere for solutions.

Those who say that Hollywood, particularly in the past 20 years, has created a culture of violence have forgotten that expressive works — ranging from Homer to the Bible, Shakespeare and Renaissance painters — have depicted violence in brutal detail for thousands of years. And long before Hollywood became a target for blame, motion pictures had for decades depicted inhumane violence in such films as “Birth of a Nation,” “Grand Illusion,” “On the Waterfront” and “Lawrence of Arabia.”

A threshold concern with using the legal system against content creators is that there is no consensus among social scientists as to the effect on individual behavior of viewing violent motion pictures or other expressive works. It is not asking too much to require a meaningful causal link between one and the other before legislation or legal liability are to be imposed.

Most importantly, there is the First Amendment. Our founders established more than 200 years ago that the government could pass no law restricting the freedom of speech. The Supreme Court has from time to time given guidance on what that principle means, including when concerns arose that speakers had said things that could cause others to act violently. The rule of law that governs here, from the Court’s 1969 Brandenburg v. Ohio decision, is that a filmmaker can have liability for the violent acts of another only if the work intentionally incites imminent unlawful action and is likely to do so.

That is a very high bar to imposing liability, as it should be. As a practical matter, it means that unless the filmmaker or the content “tells” the audience to leave the theater and engage in violent action, the fact that a motion picture depicts violence, and the fact that some unhinged person later claims that the film “inspired” the crime, are not enough to impose liability on the filmmaker.

For that reason, cases such as the one filed against Oliver Stone and the studio that produced “Natural Born Killers,” in which the family of a murder victim claimed that the perpetrators were “acting out” what they saw in the movie, were decided in favor of the defendants without having to impanel a jury. No matter what one thought of the depictions of violence in that film, it contained nothing close to an exhortation to the audience to imminently commit acts of violence. In fact, as in similar cases, years had transpired between the release of the motion picture and the criminal conduct.

Aware that the First Amendment protects the content of a motion picture, Congress and state legislatures have reacted to these tragedies by asking whether restrictions should be placed on the marketing of, and access to, works that depict violence.

In 1999, following the shooting at Columbine High School, President Clinton directed the FTC and the Dept. of Justice to study whether entertainment that depicts violence was being improperly marketed to children. The studios, record companies and videogame publishers turned over marketing plans, media buys and other documents. The government issued a report and has conducted follow-up investigations every few years thereafter.

Despite calls to regulate how the industry marketed violent content, the government recognized that the voluntary system the industry imposed on itself, starting with the film ratings system, did its job. To make that process the subject of a government takeover would require the creation of a “Ministry of Culture” and the imposition of subjective criteria that inevitably would run headlong into the First Amendment.

None of this is to say that the entertainment industry should have no part in the national conversation about acts of violence that horrify us. But turning to the courts or Congress to impose liability on the industry for such acts is not a solution to this problem. The industry is fortunate that the Supreme Court has made that clear.