The EPA did something very unusual when it released its Clean Power Plan earlier this month. The agency also released a 104 page legal memorandum arguing that its plan to regulate greenhouse gas emissions from existing power plants is legal under the Clean Air Act. I’ve been involved in dozens of EPA rulemakings, and I’ve never before seen EPA release what amounts to a legal brief with a proposed rule.

Nonetheless, all of EPA’s early legal work might just pay off. In its climate proposal, the agency did something smart: It structured the rule so that if a court doesn’t agree with certain assumptions EPA made, the other parts of the rule can stand. This bit of legal foresight should allow EPA to take more legal risks in its final rule (which could lead to larger greenhouse gas reductions), without jeopardizing the plan’s overall viability in court. Read the full article.