If it weren’t for the war, the latest ruling by Israel’s Supreme Court would be the biggest news in the country in quite some time.

The ruling, released on New Year’s Day, annulled the single biggest piece of legislation passed by Israeli Prime Minister Benjamin Netanyahu’s far-right coalition. The Court’s reasoning fundamentally changes the balance of power in Israel’s democracy — so fundamentally, in fact, that some members of the elected government have vowed not to abide by it. If that happens, Israel will be thrown into a full-blown constitutional crisis.

About a year ago, Netanyahu proposed a sweeping overhaul to Israel’s judiciary — one that would, in effect, put it under his personal thumb. Mass protests succeeded in blocking most of the overhaul. Only one plank — curtailing the power of the courts to overturn government policy — actually became law, an amendment to Israel’s “Basic Laws,” the closest thing the country has to a constitution. This is the law that was just overturned by the Supreme Court.

In doing so, the Court came to two key conclusions. First, that it has the general power to overturn Basic Laws — a power it had never deployed before. Second, that this new Basic Law was threatening enough to Israeli democracy that the court was justified in overruling it.

In peacetime, a ruling this epochal would transform Israeli politics, reorienting everything around the question of the court’s new claim to power and (plausible) claim to be saving Israeli democracy.

But with the country enmeshed in an existential war in Gaza, the domestic reaction to the court’s ruling is far less explosive than it would be otherwise. Whether this lasts — or whether Israel erupts into a domestic political crisis to match its current international peril — is far from clear.

Why Israel’s Supreme Court just made history

At the beginning of 2023, Netanyahu had just returned to power after roughly one year in opposition. His new coalition, the most far-right in Israeli history, was united around one cause: reining in an independent Supreme Court that got in the way of their ambitions. In January, Justice Minister Yariv Levin unveiled a judicial reform package that would impose sweeping political controls on the judiciary — granting the Knesset, Israel’s parliament, new powers to appoint justices and even overrule Supreme Court decisions by a simple majority vote.

Leading Israeli and international legal observers saw the plan as a naked power grab. Ruling Israeli coalitions are already extremely powerful by international standards: the country lacks checks and balances like a formal constitution, a Senate-style upper house, a federal system, or a separately elected chief executive. The judiciary is pretty much the only check on what majorities do: if Netanyahu succeeded in neutering it, he would be free to pursue his demonstrably authoritarian political agenda without constraint.

In response, Israelis filled the streets in unprecedented numbers, protests that succeeded in blocking the initial push to overhaul the court in March. So Netanyahu turned to what scholars of democratic backsliding call “salami slicing”: splitting the bill into pieces and passing them in sequence rather than all at once.

Ultimately, Netanyahu only managed to get one of these pieces passed before the October 7 attack by Hamas forced him to put off the push indefinitely — the Basic Law amendment that the Supreme Court just overturned.

Mostafa Alkharouf/Anadolu Agency/Getty Images

This new law eliminated courts’ power to overturn decisions by Israel’s Cabinet or its ministers that they find to be “extremely unreasonable,” a vague-sounding standard that has a more technical meaning in Israeli law. In the simplest terms, the courts used this doctrine to block policies when the government can’t prove that its decisions were made according to some basic standards of fair and just policymaking.

To be clear, this “reasonableness” standard is not used to review legislation. It’s a principle of administrative law, meaning it’s used to assess policy decisions by members of the executive branch — primarily, the prime minister and Cabinet members. Last January, for example, the court ruled that it would be “extremely unreasonable” for Netanyahu to appoint Aryeh Deri, a legislator convicted on tax fraud charges, to lead the interior and health ministries.

Reasonableness is a relatively common judicial principle internationally. It is especially useful in systems like Israel’s, that have few checks on arbitrary exercises of power by government officials. It is not without its flaws; the potential for judicial overreach is obvious. But instead of trying to limit reasonableness, the new Basic Law abolished it altogether — taking away one of the principal judicial tools for checking executive misconduct.

According to Israel’s Supreme Court, the danger was so huge that it justified an unprecedented step: overturning a Basic Law by judicial fiat.

“In rare cases in which the beating heart of the Israeli form of constitution is harmed, this court is authorized to declare the invalidation of a Basic Law that has in some way exceeded the Knesset’s authority,” former Israeli Supreme Court President Esther Hayut wrote in her ruling (despite having recently retired, Hayut heard the case and thus was empowered to rule on it).

This is hardly an obvious point. Typically, Basic Laws function like a constitution in Israel: when overturning legislation, the Court will frequently cite them as the legal foundation for their rulings. But in this case, 12 justices (out of 15) agreed that the Court can overturn them by appealing to Israel’s foundational identity as a Jewish and democratic state. If any law, even a Basic one, poses a serious enough threat to Israeli democracy, then the Court is justified in striking it down.

The justices were more split on whether the abolition of reasonableness was such a dire case, with a narrow 8-7 majority ruling that it was.

“In my view, it is not possible to square the amendment to the Basic Law on the Judiciary and the principle of the separation of powers and the principle of the rule of law, which are two of the most important characteristics of our democratic system,” Hayut wrote. “Such a violation at the very heart of our founding narrative cannot stand.”

Could Israel be heading for a second crisis?

With all that background in mind, you can see why this ruling is such a bombshell. The Court has just asserted a major new power and used it to rule against the government on the issue that dominated Israeli politics for the majority of last year. Under normal circumstances, this ruling would define the course of Israeli politics for the coming months.

But at the same time, there’s a general sense that the government won’t do anything about it as long as the war is going on. The government’s rhetoric, while highly critical of the court, has (somewhat cynically) blamed the court for harming wartime unity rather than calling for an immediate policy response. Even the most extreme far-right responses, such as a legislator’s tweet equating the Supreme Court to Hamas and Hezbollah, called for action against the Court after wartime.

What such action would look like is straightforward: a simple refusal to acknowledge the Court’s authority to overturn a Basic Law.

When the Court first agreed to take up a challenge to the new Basic Law after its summer passage, Netanyahu suggested he might not accept the legitimacy of a ruling overturning their ban on reasonableness. After the decision on Monday, Justice Minister Levin warned that the Court’s ruling “would not stay our hand” — seemingly a warning that his government would reject any court ruling that declares one of its future decisions as “unreasonable.”

This is the textbook definition of a constitutional crisis: a situation where two different legal authorities do not agree on what the law is or how to resolve their disagreement. Were it to happen, it would be an existential threat to the survival of Israel’s political system — a crisis the country might not be able to manage in peacetime, let alone during war.

Luckily, there is a reasonable chance it may not come to that.

The ban on reasonableness review, and the judicial overhaul in general, has long been unpopular. There is almost no chance the government will press the issue during the war with Hamas, and it may not be able to afterward. The Israeli public largely blames the government for failing to prevent Hamas’s attack on October 7, and its poll numbers are plummeting. The Economist reports that, seeing this polling collapse, some members of Netanyahu’s Likud party are privately admitting that they no longer have the juice to pick a fight over the Supreme Court.

Whether that will remain true, however, is an open question.

The future of Israeli politics will depend heavily on how the war ends and what the world looks like afterward. With Israel settling in for extended fighting in Gaza, we can’t be sure what the political climate will look like in the coming months. Developments on the ground — not just on the war front, but also in Netanyahu’s ongoing corruption trial — could well prompt the prime minister to return to his assault on the judiciary.

Right now, all we can be sure of is that the Court has just fired a major volley in a long-running war over Israeli democracy — one that will surely shape the future of that democracy for years to come.