Discussion -  In the Geier case, the Supreme Court

Discussion 2.1

 In the Geier case, the Supreme Court held that states may not regulate motor vehicle safety standards.

 How do you think states like California and Massachusetts can impose stricter emission controls on motor vehicles than the federal standard? 

For more info on the U.S. Department of Transportation standards, visit: http://www.nhtsa.dot.gov/cars/rules/import/fmvss/index.html