The Shin Bet is deeply involved in Israel’s war against Hamas in Gaza, providing intelligence and targets. By law, the agency is also tasked with protecting Israeli democracy.

The discord between Mr. Netanyahu and Mr. Bar goes to the heart of a broader battle playing out over the nature and future of Israel’s democracy and the rule of law. Critics of Mr. Netanyahu’s ruling coalition, the most right-wing and religiously conservative in Israel’s history, accuse it of working to reduce the authority of independent state watchdogs and to remove checks and balances on the powers of the government, which holds a narrow majority in Parliament.