The Trump administration and California argued in front of a federal judge Wednesday over whether the Environmental Protection Agency’s efforts to reclassify Clean Air Act waivers, granted to the state as rules, constitute final agency action.

At the heart of California’s case is the EPA’s June announcement that four waivers already granted to the state under the Clean Air Act, are rules instead of waivers and that as a result, the agency sent them to Congress as required. Classifying the waivers, which allow the state to set stricter air quality standards than the federal government, as rules theoretically allows Congress …