The Supreme Court on Tuesday effectively struck down the heart of the Voting Rights Act of 1965 by a 5-to-4 vote, ruling that Congress had not provided adequate justification for subjecting nine states, mostly in the South, to federal oversight.

“In 1965, the states could be divided into two groups: those with a recent history of voting tests and low voter registration and turnout, and those without those characteristics,” Chief Justice John G. Roberts wrote for the majority. “Congress based its coverage formula on that distinction. Today the nation is no longer divided along those lines, yet the Voting Rights Act continues to treat it as if it were.”

Chief Justice Roberts said that Congress remained free to attempt to impose federal oversight on states where voting rights are at risk but must do so based on contemporary data. When the law was last renewed, in 2006, Congress relied on data from decades before. The chances that the current Congress could reach agreement on where federal oversight is required are, most analysts say, small.

Justice Antonin Scalia, Anthony M. Kennedy, Clarence Thomas and Samuel A. Alito Jr. joined the majority opinion. Justice Ruth Bader Ginsburg dissented, joined by Justice Stephen G. Breyer, Sonia Sotomayor and Elena Kagan.

The majority held that the coverage formula in Section 4 of the Voting Rights Act, originally passed in 1965 and most recently updated by Congress in 1975, was unconstitutional. The section determines which states must receive pre-clearance from federal authorities.

The court did not strike Section 5, which sets out the pre-clearance requirement itself. But without Section 4, which determines which states are covered, Section 5 is without significance — unless Congress chooses to pass a new bill for determining which states would be covered.

Click here for the full story.