The city of Chicago sued to stop the operation of the Commonwealth Edison Company’s coal-burning, electricity-generating plant in nearby Hammond, Indiana. Chicago claimed that the plant emitted too much smoke, sulfur dioxide, and other harmful substances. The city also claimed that the plant was a common-law public nuisance because it caused “an unreasonable interference with a right common to the general public” to clean air. Edison argued that it had spent much money to reduce harmful emissions and that the emissions were now well below the levels prescribed by federal clean air regulations and by the city of Hammond. Edison also pointed out that “unpleasant odors, smoke, and film” already characterized the area in which the plant was located. The trial court refused to issue an injunction. Therefore, the city of Chicago appealed to a higher court, which affirmed (upheld) the trial court. How can this legal action be ethically justified? (City of Chicago v. Commonwealth Edison Company, 321 N.E.2d 412, Ill.)