Hypocritical attacks on Israel are common, but Sarah Leah Whitson takes them to a new level. As Middle East and North Africa director of Human Rights Watch, she is one of the sharpest critics of the Jewish state’s presence in the West Bank, promoting boycotts and international prosecution for the supposed crimes of occupation and settlement. Yet elsewhere Ms. Whitson strongly supports settlements in occupied territories—suggesting that she and her colleagues don’t take their own legal claims against Israel seriously.

The settlements...