Israel's Supreme Court heard arguments on Tuesday against a bid by Prime Minister Benjamin Netanyahu's government to curb the court's powers, part of a judicial overhaul that has divided the nation, sparked months of protests and worried Israel's allies.
The court's 15 judges were hearing challenges by watchdog groups against a amendment passed in July ending the Supreme Court's ability to overturn some government decisions when it deems them "unreasonable".
Although other tools for voiding executive decisions remain in place, opponents say the amendment removes a vital check and balance in Israel's political system. The government says its aim is to stop political overreach by unelected judges.
A ruling is not expected for weeks or months, but the showdown pitting the judiciary against the executive and legislature has gripped the nation. The hearing has been given wall-to-wall television and radio coverage.
"Can you really hold a discussion of this question, without bias or predisposition, given that it is a matter of your status, your honour?" Simcha Rothman, a lawmaker in Netanyahu's religious-nationalist coalition and architect of the judicial overhaul, asked the court.
Chief Justice Esther Hayut responded: "We are not addressing ourselves - neither our status nor our honour... We are addressing the public's vital interests."
As the hearing began, the shekel, which last week hit its lowest level in three years, weakened 0.2% in early trading.
The crisis has split Israeli society, while the US and other Western allies have voiced concern about the impact of the judicial changes on Israel's democracy.
Israeli business and civil society groups say the judicial overhaul risks undermining the economy. Some Military reservists, who protest leaders say number in the thousands, have stopped reporting for duty in protest. Netanyahu and some in the military say their action threatens national security.
Justice Minister Yariv Levin, another architect of the judicial overhaul, said the Supreme Court session was "a mortal blow to democracy and the standing of the Knesset".
The government says the Supreme Court has no authority to review amendments to Basic Law, which has a quasi-constitutional status in a country without a formal constitution.
Yair Lapid, centrist head of the parliamentary opposition, said the amendment was "warped and thuggish", writing on social media platform X, formerly known as Twitter: "It's not worth getting into a national quarrel over such legislation."
Netanyahu, who is on trial for corruption charges he denies, says the judicial changes are meant to balance out branches of government. He has been hazy when asked whether he would abide by a ruling that would quash the new law.
Chief Justice Hayut asked Yitzhak Bart, a parliamentary legal adviser who spoke for the government's position: "Who should oversee reasonable conduct on the part of the government? Do you agree that there should be law - but not an adjudicator of the law?"
Bart said the court retained other ways to intervene in government decisions.
The coalition started its judicial campaign in January.
Since then, many Israelis have been rattled by the public protests that have extended to the military amid worries about potential flare-ups with the Palestinians, Iran and the heavily armed Iran-backed group Hezbollah in neighbouring Lebanon.
Netanyahu has said some of the original proposals have been scrapped. But his efforts to reach compromise agreements with opponents on the overhaul have so far been fruitless, adding to fears that Israel's worst domestic crisis in years will deepen.
With two more appeals scheduled this month and with the court ruling possibly ruling as late as January, analysts said there was till time both sides to reach agreement on changes.