Northwest Austin Municipal Utility District Number One v. Holder
http://laws.findlaw.com/us/000/08-322
8-1 ruling by the Supreme Court that an Austin, Texas municipal utility district could apply to opt out of the provisions of the Voting Rights Act. The court declined to use the case to declare unconstitutional the provisions that require 16 mostly southern states to gain Justice Department approval to prevent discriminatory voting practices. From Findlaw.com
