Domestic violence has become a hot topic in the world of professional sports in the United States. With several recent domestic violence incidents, this is for good reason.The Floyd Mayweather Jr.-Manny Pacquiao boxing match earlier this month was the latest illustration, with Mayweather’s history of violent behavior thoroughly reported in the New York Times and other publications. A quick Google search provides several other recent examples.The statistics from football, one of the four major U.S. sports, show that …