In Minnesota's tobacco trial, tobacco companies today refuted claims they conspired to violate state antitrust laws. An antitrust expert testified such a conspiracy makes no economic sense. Minnesota Public Radio's Laura McCallum reports... Vanderbilt University economist David Scheffman testified he found no evidence of a tobacco industry conspiracy to suppress competition. The state's antitrust expert, Brandeis economist Adam Jaffe, testified earlier in the trial tobacco companies agreed not to compete to develop safer products, because that would mean admitting their cigarettes were unsafe. But Scheffman said su