"The rhetoric is just ramped up so negatively, so high, that we have got to shut this down," is how Rep. Robert Brady, D-Pa., put it, though there's no evidence that the killer was at all influenced by any such speech.
There's no specific text yet, so it's not clear exactly what language or images the bills would try to criminalize. What is clear, however, is that any such proposal either would be repetitive of existing law or would violate the First Amendment.
The Supreme Court has ruled that threatening language loses First Amendment protection only if it is intended to communicate a "true threat" -- "a serious expression of an intent to commit an act of unlawful violence to a particular individual or group of individuals."
The court even held that the Constitution protects a statement like "If they ever make me carry a rifle, the first man I want to get in my sights is L.B.J.," said at an anti-war rally in the late 1960s. That was, the court held in a 1969 ruling -- Watts v. United States -- just rhetorical excess, not a true threat.
Likewise, "politics as combat" language doesn't strip speech of constitutional protection, if in context the speech can't reasonably be seen as a statement of intent to violently attack someone. And such language has been commonplace in American political life, from the early Republic to the present -- consider, for instance, President Barack Obama's line: "If they bring a knife to the fight, we bring a gun."
If the speech is reasonably seen as expressing an intent to kill someone, it should be punishable. But distributing true threats on the Internet, radio or television is already a federal crime. There's no need for a new law to deal with this.
What if the concern isn't that legislators will feel threatened by the use of combat imagery about them, but rather that some viewers might be moved by such statements to attack the politicians?
Even then, such speech would be constitutionally protected.
In a 1969 case -- Brandenburg v. Ohio -- the Supreme Court held that the First Amendment protects speech, even if there's a fear that the speech might promote violence sometime in the future. As the court put it, such language could only be punished if it was intended to incite "imminent lawless action and is likely to incite or produce such action." "Imminent" here refers to action that is intended to happen in the next few hours or days, rather than at "some indefinite future time." (This is called the "incitement" exception to the First Amendment.)
But none of the imagery discussed in this controversy was at all intended to produce crime, much less imminent crime. And the court's Brandenburg ruling means that speech can't be banned just because a few kooks or extremists might be moved to commit a crime as a result of seeing the speech. (Again, there's no evidence that this in fact happened here.)
Despite that, the court concluded that even violent-sounding speech must remain constitutionally protected, unless it fits within the narrow exceptions for true threats and incitement.
The same judgment remains correct today. Our First Amendment rights cannot be restricted because of the lunacy or extremism of a killer.
Eugene Volokh is a professor of law at UCLA. He blogs at volokh.com.