How did the 2013 Supreme Court ruling invalidate the heart of the Voting Rights Act of 1966

The Supreme Court on Tuesday effectively struck down the heart of the Voting Rights Act of 1965 by a 5-to-4 vote, freeing nine states, mostly in the South, to change their election laws without advance federal approval.

The court divided along ideological lines, and the two sides drew sharply different lessons from the history of the civil rights movement and the nation's progress in rooting out racial discrimination in voting. At the core of the disagreement was whether racial minorities continued to face barriers to voting in states with a history of discrimination.