Can carbon-reducing projects "offset" a company's emissions? "The reality has been less encouraging," according to a Science magazine editorial by Cary Coglianese, a law/political science professor at University of Pennsylvania, and Cynthia Giles, a former senior advisor at the U.S. Environmental Protection Agency. In a new paper published Wednesday, they found that more than half of all currently-certified carbon auditors signed off on projects later found to be "overclaiming" carbon benefits.