Few other than Orthodox Jews would recognize the word "eruv." Fewer still would recognize its physical embodiment — let alone comprehend its function. But when proponents ask a town for consent to erect one, controversy at times erupts. In recent years, Westhampton Beach, N.Y., and its neighboring communities on Long Island, Quogue and Southampton, have been caught up in a battle over whether to allow an eruv to be built within their precincts. Now, while even children in the area are likely familiar with the term, eruvin remain a focus of fear, misunderstanding and hostility among residents, including some Jews.

Opponents express concerns that an eruv would become a magnet for Orthodox families. They raise such specters as forced closure of shops on Saturdays (highly unlikely in weekend and summer destinations), a steep decline in property values and a change in the "character" of the community. Two federal lawsuits raising constitutional and statutory issues relating to the conflict have recently been given a green light to proceed to trial. (A third was dismissed.) Whatever the outcome, the underlying five-year conflict risks leaving permanent scars on the body politic.

What is an eruv? Physically, it consists of "lechis," unobtrusive plastic strips ordinarily affixed to utility poles. (If different kinds of posts are used, these must be linked by something similar to wire, like string, in order to create a boundary.) Conceptually, to the Orthodox mind, it is an extension of the home. An ancient device, it solves the problem of reconciling the dictate to attend synagogue on the Sabbath with the ban on working that day. Since "work" includes such tasks as pushing walkers or strollers, and even employing canes or wheelchairs, this legal fiction lets its adherents use modern conveniences or necessities without contravening their faith.

Even though the Orthodox pay for building and maintaining eruvin, religious and pragmatic considerations compel a modicum of government involvement. For one thing, for an eruv to be deemed effective, Halachic law demands some sort of official approval. For another, as a practical matter, affixing lechis to telephone poles often requires permission from public utilities as well as conformity with local sign and right-of-way laws. Hence, the potential for divisive First Amendment disputes.

These are playing out now on Long Island. In the recently dismissed action, Jewish People for the Betterment of Westhampton Beach urged that an eruv would amount to a forbidden establishment of religion. In another lawsuit, the East End Eruv Association relies on the right to free exercise and contests establishment arguments mounted by the village and town defendants. Verizon Communications Inc. and Long Island Lighting Co., which have entered into licensing agreements with the association for use of their poles, have also sued the municipalities. They seek the court’s guidance regarding their obligations since they are in an unenviable position: caught between the Scylla of fines if they allow installation of the lechis and the Charybdis of claims of breach if they do not.

Prevailing establishment doctrine looks to whether a reasonable informed observer, aware of pertinent history and context, would view the challenged government action as endorsing religion. Given the defendants’ strong opposition to the creation of an eruv, its construction would seem unlikely to signal municipal approbation. Moreover, courts have consistently held eruvin to constitute a valid free exercise accommodation. Yet some consider the lechis to be religious symbols, which are literally "entangled" with — because affixed to — public property, for entirely sectarian reasons. Thus regarded, they would appear to violate the standards of the seminal Lemon v. Kurtzman, 403 U.S. 602 (1971).

Here the authorities wish to deny an accommodation that, arguably, the establishment clause does not forbid. Does the free exercise clause command it? The opponents would bar the planned eruv in supposed reliance on ordinances governing sign displays or rights-of-way. Under Employment Division v. Smith, 494 U.S. 872 (1990), a "neutral" and "generally applicable" law that only incidentally burdens religious conduct does not infringe on free exercise. But if the law is not general or discriminates against religion, its use is subject to strict — ordinarily, fatal — scrutiny. (Further, the Religious Land Use and Institutionalized Persons Act of 2000 now also imposes this stringent approach.) In Tenafly Eruv Association Inc. v. Tenafly, 309 F.3d 144 (3d Cir. 2002), the U.S. Court of Appeals for the Third Circuit invoked strict scrutiny to bar interference with lechis when the record revealed that Tenafly, N.J., allowed other attachments to poles like house numbers and directional signs. Similar contentions of inconsistency are being made in this litigation; if proven, East End Eruv Association should prevail.

But who wins if religious bad feeling continues to pervade these communities? One can only hope that with the eventual resolution of the suits, calm voices reassert the values of tolerance and diversity.

Vivian Berger is professor emerita at Columbia Law School.