Professional football has a problem: the specter of mass brain damage among current and former players. So far, the steady trickle of disturbing revelations has had no apparent effect on ticket sales or TV ratings. What it has done, though, is more ominous: It has invited lawsuits.

As Steve Chapman observes, if football falls into decline, it may not be the result of fans turning away, athletes avoiding it, or parents forbidding it. It may be from lawyers representing players who sustained chronic traumatic encephalopathy and expect to be compensated for the damage.