I have become increasingly concerned that EPA has itself paid too little attention to the science of global warming. EPA and others have tended to accept the findings reached by outside groups, particularly the IPCC and the CCSP, as being correct without a careful and critical examination of their conclusions and documentation. If they should be found to be incorrect at a later date, however, and EPA is found not to have made a really careful independent review of them before reaching its decisions on endangerment, it appears likely that it is EPA rather than these other groups that may be blamed for any errors. Restricting the source of inputs into the process to these these two sources may make EPA’s current task easier but it may come with enormous costs later if they should result in policies that may not be scientifically supportable.