Liberal Justice Elena Kagan sharply criticized the Supreme Court’s conservative majority Tuesday, saying it undermined democracy in a series of rulings, including several that have prompted a new wave of legislative map-drawing that has increasingly eliminated competitive districts. Kagan, who has dissented in those cases, also took aim at the majority for striking down campaign finance restrictions and, as she put it, the “evisceration” of the landmark 1965 Voting Rights Act that was enacted to protect minority voters. “Part of the reason why the court got it wrong was a kind of lack of the appropriate concern or understanding of...