 versus the Natural Resources Defense Council, holding that federal agencies have the power to interpret laws passed by Congress whenever there's any gray area. Conservatives generally said that gave far too much power to regulatory agencies such as the Environmental Protection Agency. The Biden administration argued that overturning the Chevron doctrine, which has been in place now for 40 years, would generate a convulsive shock to the legal system. Now we'll find out just what that convulsive shock looks like. CNBC's Eamon Javers.