Gali Baharav-Miara, Israel’s first female attorney general, has stopped many of the government’s efforts to remove constraints on its power. As the country heads into elections next month, she is bracing for what could be her biggest battle yet. Her admirers see her as a solitary heroine, standing in the way of Israel’s most right-wing and religious government as it pushes the country toward authoritarianism. Her detractors see her as a public enemy, blocking Prime Minister Benjamin Netanyahu’s attempts to supercharge majority rule and rein in a power-mad, left-leaning judiciary.

What no one disputes is that Gali Baharav-Miara, 67, the first woman to serve as the attorney general of Israel, has almost single-handedly defeated many of the government’s efforts to undercut the Supreme Court, crack down on the news media and free itself of some of the biggest checks on its own power. Now, Ms. Baharav-M