In The Hill, Richard Revesz argues that the high court has struck only a minor blow against the EPA's mercury rule

In the final ruling of an historic Supreme Court term, the Obama administration was handed a loss on Monday, but the fallout will likely be minimal. In a 5-4 decision written by Justice Antonin Scalia, the court found that the Environmental Protection Agency (EPA) should have considered costs when it first began the regulatory process for its Mercury and Air Toxics Standards.