Refusing to stand for the National Anthem in protest, as San Francisco 49ers quarterback Colin Kaepernick and now many others have been doing before games, is "dumb and disrespectful" but of course is constitutionally protected free expression, U.S. Supreme Court Justice Ruth Bader Ginsburg says.

"If they want to be stupid, there's no law that should be preventive. If they want to be arrogant, there's no law that prevents them from that," she tells Katie Couric in a Yahoo News interview. "What I would do is strongly take issue with the point of view that they are expressing when they do that."

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AP photo/Ben Margot

Credit: Jennifer Brett

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Credit: Jennifer Brett

As controversy over Kaepernick's decision spread , the NFL said in a statement: "Players are encouraged, but not required, to stand during the playing of the National Anthem."