The plan working its way through the United States Congress (the Waxman-Markey bill) would initially give away 85% of the permits, impose a complex set of regulatory policies, and allow companies to buy CO2 offsets (e.g., by paying for the planting of trees) instead of reducing their emissions or buying permits. Such complexities make it impossible to compare the impact of CO2 policies among countries, which in turn would invite those who want to protect domestic jobs to argue for higher tariff levels.