Black treated Johnny Cochran, O.J. Simpson's attorney, who died of a brain tumor in 2005. Cochran's widow, Dale, will also be on the show. "There's a significant correlation between the side that one uses [a] cell phone on and the side that you develop the brain tumor on," Black told CNN's Gupta three years ago. Taking an opposing view was Howard Frumkin of Emory University and more recently CDC. "This is a very low probability kind of a thing approaching zero probability," Frumkin said, "There's no evidence to support the idea that Mr. Cochran's brain tumor resulted from cell phone use."