In 1990, Congress passed legislation directing the Immigration and Naturalization Service to grant permanent U.S. residency to people whose presence in the United States would be in the national interest. But Congress never defined what constituted the national interest.

As a result, a few hundred clerks who work at INS offices in Texas, California, Nebraska and Vermont are left to make up their own definitions. Observers say the outcomes are often bizarre.

• In the national interest, the INS has granted permanent residence to an acrobat from Russia who plays a horn while flying through the air, a Korean golf course designer, a Russian ballroom dancer and a Ghanaian drum maker.

• In adopting the national interest visa provision, Congress set aside 140,000 spots for permanent workers in all categories.

• Two loopholes were also created, allowing the INS to admit people who were either "extraordinary," such as Oscar winners or Nobel laureates, or were "exceptional" -- a category much more difficult to define.

• The INS doesn't count the applications it approves in either category, but lawyers estimate they send in about 10,000 a year in each.

Immigration lawyers report that INS personnel whose job it is to accept or reject applications are notoriously inconsistent. Hit with a rejection from one clerk, a lawyer will write up another cover letter and send the application back. As often as not, lawyers report, a second clerk will approve it.

In 1995, the INS sought to define the "national interest," but its proposals were jeered at by the immigration bar and withdrawn. The service is trying again by selecting a single denied application as a model and using it as a legal precedent.