George W. Bush is not the only politician having trouble these days in getting a Supreme Court nominee accepted. Israel’s Minister of Justice Tsipi Livni is another.

Of course, there are some major differences between Mr. Bush’s and Ms. Livni’s difficulties, starting with the nominee – in both cases a woman – herself. Harriet Miers was by all accounts supremely underqualified to be a United States Supreme Court justice. If she had any clear opinions about the legal issues that concern America, she had managed to keep them entirely to herself.

Ruth Gavison, on the other hand, Justice Minister Livni’s controversial candidate for a seat on Israel’s High Court of Justice, would seem to be overqualified. Or at least her problem is that, a professor of law at the Hebrew University of Jerusalem, she has for many years been systematically thinking and speaking out on constitutional and juridical issues – and what she has thought and said has not pleased everyone.

And yet there are similarities between the two cases, too. In both of them, a society badly split between liberal and conservative population groups, many of the latter holding strong religious beliefs, has become dependent on its highest legal forum to adjudicate social and ethical questions that elected legislatures have not adequately dealt with – and in both cases, the political fallout has been great. Nowhere else in the democratic world has the role of a supreme court become as hotly debated as in Israel and America, and nowhere else is every candidate for such a court scrutinized as closely for his or her political views.

Professor Gavison’s views might be roughly classified as “conservative,” although in the Israeli context that does not mean exactly what it does in the American one. Although she is not associated with the political right, she has consistently opposed the judicial activism of Israel’s high court as manifested in the past two decades under the leadership of Chief Justice Aharon Barak. Justice Barak, who has been compared by many observers to Earl Warren, took a court that, until his long term at the head of it, sought to avoid hearing cases with highly political implications, and turned it into a body that now vies with Israel’s Knesset in shaping social policy.

Precisely the fact that Israel does not have a written constitution to set the boundaries between the executive, legislative, and judicial branches of government encouraged the Barak court to intervene in areas, as disparate as the regulations for conversion to Judaism and the route of Israel’s West Bank security fence – that would not traditionally have been considered its domain. This is a tendency that Professor Gavison has been sharply critical of.

Chief Justice Barak, a political liberal in outlook, has a say in nominations to his court that Supreme Court judges in the U.S. do not have, since in Israel high court nominees need to be approved not by the Knesset, but by a nine member committee that includes three high court justices. And Mr. Barak has made it clear that he intends to vote against the Gavison’s nomination and to persuade his fellow committee members to do the same because, as he has put it, she would be coming to the court with a preconceived “agenda” that would preclude objectivity on her part. A high court justice, Chief Justice Barak is in effect saying, should not have too many opinions in advance.

And yet clearly, what bothers the chief justice is not that Ruth Gavison has an “agenda,” but that the agenda she has is opposed to his own. As he sees it, she constitutes a serious threat. Although not every judge on Israel’s 11-member high court has agreed with Mr. Barak on everything, the opposition to his own liberal agenda has on the whole been sporadic and unorganized, with no single figure on the court playing a dominant role in it. Professor Gavison would in all likelihood become that figure. She has the intellect, the point of view, and the combative spirit for it.

And yet as much as one may sympathize with her belief that the courts of Israel should not aspire to be “the supreme moral arbiter of society,” there is more to be said for a policy of judicial activism in Israel than in the United States. The lack of a constitution is just one reason for this. Israel’s politics are a second.

These are politics in which neither side, neither the conservative nor the liberal, is ever firmly in control of the legislative process. Unlike America’s Congress or state legislatures, where either the Democrats or the Republicans are in power, the Israeli system of proportional representation, which results in ruling coalitions in which many parties are represented, almost never produces governments capable of taking clear stands on divisive social issues and passing legislation to deal with them. The Knesset’s usual way of dealing with matters like civil liberties, synagogue-state relations, citizenship and marriage laws, et cetera, is either to leave them to be determined by administrative fiat or to do nothing at all until they are thrown into the laps of the courts.

Judicial activism in such a situation is as much a question of practical necessity as of legal philosophy. Just last week, for example, Israel’s high court issued a temporary injunction against the interior ministry, barring it from deporting, on its own initiative, Israeli born or raised children of illegal foreign workers. And yet although the whole question of immigration to Israel is one of the most vexed ones the country is faced with, the Knesset has never once sought to pass legislation of its own in the area.

Professor Gavison should be on Israel’s court. Her voice deserves to be heard there. But until electoral reform in Israel produces a different kind of legislative branch, the country will have to keep looking toward the judicial one.

Mr. Halkin is a contributing editor of The New York Sun.