WASHINGTON - States can't demand proof of citizenship from people registering to vote in federal elections unless they get federal or court approval to do so, the Supreme Court ruled Monday in a decision complicating efforts in Arizona and other states to bar voting by people who are in the country illegally.

They would need permission from a federally created panel, the Election Assistance Commission, or a federal court ruling overturning the commission's decision, to make tougher requirements stick.

Justice Antonin Scalia, who wrote the court's majority opinion, said federal law "precludes Arizona from requiring a federal form applicant to submit information beyond that required by the form itself."

BOSTON - Tuukka Rask watched most of the action at the other end of the ice.

The Bruins goalie stopped 28 shots for his third career playoff shutout, helping Boston beat Chicago 2-0 on Monday night to take a 2-1 lead in the Stanley Cup finals.

After playing four extra periods in the first two games, the Bruins made an early night of it with second-period goals by Daniel Paille and Patrice Bergeron.