191 F.3d 516 (4th Cir. 1999) UNITED STATES OF AMERICA, Plaintiff-Appellee,v.SMITHFIELD FOODS, INCORPORATED; SMITHFIELD PACKING COMPANY, INCORPORATED; GWALTNEY OF SMITHFIELD, LTD., Defendants-Appellants.MICHIGAN CHAMBER OF COMMERCE; PENNSYLVANIA CHAMBER OF BUSINESS AND INDUSTRY; COLORADO ASSOCIATION OF COMMERCE AND INDUSTRY; AMERICAN AUTOMOBILE MANUFACTURERS ASSOCIATION; AMERICAN MEAT INSTITUTE; AMERICAN PETROLEUM INSTITUTE; INDEPENDENT PETROLEUM ASSOCIATION OF AMERICA; INTEGRATED WASTE SERVICES […]