A string of new laws passed this year by Israel's right-leaning Knesset has triggered an unusually rancorous debate here over where to draw the line on free speech, exposing shifting sentiments about a core democratic ideal.

The latest battle erupted with the approval this month of a law that created civil and financial penalties against those who voice support for boycott campaigns targeting Israel or its institutions, including West Bank settlements that many in Israel and around the world oppose as an obstacle to peace.

Free-speech advocates blasted the law as an unprecedented assault on the right to criticize the government, while proponents praised it as a patriotic defense of Israel's image.

It came on the heels of other measures that critics say erode Israel's democratic foundations, including ones that penalize certain groups that publicly commemorate Nakba Day, marking the 1948 Palestinian displacement; legalize "admissions committees" to screen would-be residents of small Israeli towns; and require non-Jewish immigrants seeking citizenship to take a loyalty oath to Israel as a "Jewish and democratic" state.

Another bill that would have launched government investigations of mostly left-wing advocacy groups failed this month, but proponents are vowing to reintroduce it.

Israel's Supreme Court probably will decide the fate of the new rules. But many of the controversial measures received solid public support, reflecting a growing ambivalence in Israel over free-speech rights.

Polls by the Israel Democracy Institute, a think tank, found that public support for free-speech rights is declining in Israel and that more than one in three Israelis now say there is "too much" free speech. Support for free expression "regardless of their views" dropped from 90% in 1999 to 74% in 2009. And intolerance for government criticism is rising. In 2009, 58% agreed that it was OK to prohibit "harsh criticism of Israel in public," compared with 48% in 2003, according to the IDI.

"We never had a fundamental problem with freedom of speech until now," said Amir Fuchs, a constitutional law researcher at the IDI. "It's clear that the people of Israel are becoming less democratic and more conservative."

Supporters of the recent laws call such criticisms exaggerated, saying Israel continues to support a vibrant environment for free speech, an ideal that many say is rooted in the Jewish religion's tradition of encouraging debate and intellectual questioning.

Examples of free speech in Israel are easy to find.

Arab-Israeli lawmakers frequently attack the government as "racist" on the Knesset floor. Breaking the Silence, a group of former soldiers, is allowed to publicize alleged misconduct by the military. Newspaper pundits don't hesitate to launch character attacks against the prime minister.

At the same time, Israelis accept limits on free expression that other democracies would reject.

A military censorship board reviews press reports before publication to screen out information it deems possibly compromising of national security. Courts make liberal use of gag orders to suppress or delay disclosure of sensitive or embarrassing cases.

"Free speech is very much entrenched in the Israeli psyche and society," said Amnon Rubinstein, a law expert and former Knesset member with the liberal Meretz Party. "But Israelis have mixed feelings about free speech when it comes to issues involving the Arab-Israeli conflict and national security."

Israel's struggle to forge a free-speech balance dates to its founding. The Declaration of Independence guarantees a variety of civil rights, including equality, freedom of conscience, and protection against discrimination based on race, sex or religion. But it says nothing about free speech or free expression.

Rubenstein said the issue probably was supposed to be tackled in a written constitution. But Israel's first Knesset and every one since has resisted calls to formulate one, largely because of deep-seated differences between Israel's secular and religious communities.

Instead, the Knesset over the years passed a series of so-called basic laws, which were intended to eventually become chapters in a constitution. But those laws say nothing explicitly about free speech. Efforts to pass a free-speech protection in 1992 failed amid opposition by religious groups.

As a result, free-speech rights in Israel stem from the Supreme Court, which has ruled that such protections are integral to a modern democracy. But legal experts say the basic laws, which can be easily changed by the Knesset, are a poor substitute for a written constitution.

"Rights such as freedom of expression and equality are still missing from basic law," said Suzie Navot, head of the public law division at the College of Management Academic Studies Law School. "It's handicapped because it's incomplete."

Religious leaders say their opposition to passing a blanket free-speech law stems from concern that it might weaken religious values and open the door to hot-button issues such as gay rights, Christian missionaries, the spread of non-Orthodox strains of Judaism and anti-Semitism. Ultra-Orthodox groups worry that such things could become more entrenched in Israel if protected by a free-speech law.

"As it is, the Haredi community is struggling with the impact of various anti-Semitic or extreme secular elements constantly trying to undermine Jewish values," said one influential ultra-Orthodox rabbi, who asked not to be identified given the sensitivity of the issue. "Coping with these challenges would be even harder if we were to have to fight an official law."

Free-speech advocates say the recent moves in the Knesset highlight the need to enshrine such rights in law, warning that Israel's acceptance of limits on one form of expression could set a precedent.

"It might start as a way to silence the other side of the political map," said Fuchs, of the IDI. "At first it was about the Arabs. Then people saw that the boycott law was about shutting their mouths.

"People need to understand that eventually it will come around to them."