The Bush administration will reverse course and bring new court cases against violators of power-plant emissions standards, according to EPA Administrator Mike Leavitt. Just three months ago, it was revealed that the administration had decided to stop investigating 70 power plants suspected of violating clean air standards, and would consider dropping 13 other cases that were referred to the Justice Department. This decision followed EPA’s action weakening its New Source Review (NSR) program, which governs power-plant emissions. Past violations, the administration concluded, would be judged by the new, weaker standard -- even though it was not the law at the time. Then, a day before Christmas, a federal appeals court temporarily blocked the administration from implementing the NSR rollback. As a result, Leavitt said, EPA would aggressively enforce the existing rule until the case is resolved.