The rallies on Saturday marked the 28th straight week of demonstrations against Netanyahu’s plan and come days after his government gave initial approval to a key bill which is part of the overhaul.
The bill, which was approved in its first reading, would reduce the “reasonability” clause through which the judiciary can strike down government decisions.
It would also give the government a greater say in the appointment of judges.
The bill still needs to be approved in two more votes, expected by the end of the month, before it becomes law.
In Tel Aviv, protesters unrolled a large banner reading “SOS” and threw paint powder into the sky, streaking it pink and orange.
“Handmaids” – women dressed in red robes as characters from the dystopian novel and TV series The Handmaid’s Tale – once again took to the streets. Their jarring appearance is meant to drive home the notion that, if the overhaul passes, women could be stripped of their rights.
“This is a battle for the country, we want to keep Israel democratic and the dictatorship laws won’t pass here,” protester Nili Elezra, 54, told the AFP news agency.
Passing the laws would harm Israel’s financial and global standing, she said.
“Things will be bad. People are already leaving, money is being lost, investors are fleeing, the world doesn’t want to talk to us, nobody is happy with what’s going on here,” she said.
Saturday’s protesters in Tel Aviv were joined by others across the country. Protesters brandished lit torches outside Netanyahu’s home in Jerusalem and demonstrated in the coastal cities of Herzliya and Netanya.
Protest organisers also said they would hold a “day of disruption” on Tuesday if the Israeli leader continues to move ahead with the plan.
The protests came as Netanyahu remained in hospital after getting admitted earlier on Saturday for dehydration. The 73-year-old sought treatment after suffering a dizzy spell and having spent the previous day in the sun without drinking water.
He later released a video from the Tel Aviv hospital saying he felt good.
Netanyahu was to spend the night in the hospital, according to his office, and a weekly Cabinet meeting scheduled for Sunday was pushed to Monday.
His government’s decision to push ahead with the judicial overhaul – which the Israeli leader suspended in March amid protests and international criticism – came after cross-party dialogue on the matter collapsed last month.
Opposition to the plan, however, remains strong.
After more than six months of protests, the movement shows little sign of abating. Israel’s national labour union and its medical association have joined a long list of groups speaking out against the bill. Military reservists, fighter pilots and business leaders have all urged the government to halt the plan.
Arnon Bar-David, the head of the country’s national labour union, the Histadrut, threatened a possible general strike that could paralyse the country’s economy.
“If the situation reaches an extreme, we will intervene and employ our strength,” Bar-David said, calling on Netanyahu to “stop the chaos.”
The Histadrut called a general strike in March as the government pushed the judicial overhaul legislation through parliament after weeks of protest. The move shut down large swaths of Israel’s economy and helped contribute to Netanyahu’s decision to suspend the legislation.
The Israeli Medical Association, which represents 90 percent of Israeli physicians, joined the Histadrut on Friday, voting to “employ all available means, including significant organisational measures” to oppose the reasonableness bill.
The law will “devastate the healthcare system,” the chairman of the association, Professor Zion Hagay, said.
To protester Elad Ziv, the upcoming weeks will be crucial in stopping the legal reform.
“We have two and a half weeks to the end of parliament’s summer session and we have to block them, otherwise Israel will become a worse place,” the 45-year-old programmer told AFP.
“We do see the protest working in supporting people who are fighting,” he said.
“The numbers make a difference.”