Federal efforts to tighten the border and deport illegal immigrants are so far insufficient to satisfy states and localities, which are proposing and passing laws at record rates to take matters into their own hands.

With a proposal for comprehensive immigration reform now stalled in the US Senate, and its prospects for revival uncertain, the wave of immigration-related measures outside Washington is only likely to grow, as state and local governments balk at shouldering the economic, law-enforcement, and social costs they attribute to illegal immigrants.

Through mid-April, legislators in all 50 states had introduced a record 1,169 bills dealing with illegal immigrants – more than twice the number put forward in all of 2006. Eighteen states had enacted 57 of those bills as of April 19, two-thirds of the number of immigration laws adopted by states last year, according to a report by the National Conference of State Legislatures (NCSL) in Washington.

"I would not be surprised to see an increase above this year's historic level [of state legislation] if there's no [federal] reform," says Sheri Steisel, an immigration policy expert at NCSL. "Clearly, in areas of employer documentation, education, and healthcare we'll see even more activity next year."

Cities take action, too

Cities, counties, and towns are grappling with illegal immigration as well.

"More than 90 cities or counties have proposed, passed, or rejected laws prohibiting landlords from leasing to illegal immigrants, penalizing businesses that employ undocumented workers, or training local police to enforce federal immigration laws," said Dennis Zine, a board member of the National League of Cities and the chair of its Immigration Task Force, in testimony before a US House Judiciary subcommittee in May.

Local governments, he said, have no control over the flow of immigration but are responsible for integrating immigrants into their communities. "While immigrants have strengthened our country and our communities in innumerable ways," Mr. Zine testified, "many communities are straining to find the right approach in such an unsettled environment over immigration and federal immigration policy."

The state and local bills run the gamut of immigration-related issues, though most are intended to make life more uncomfortable for people in the United States illegally.

They also raise some thorny issues for politicians wanting to take action. For instance, if Arizona decides to sanction employers in the state for hiring undocumented workers, will the companies targeted move to a state that doesn't have such an enforcement regimen?

Such a bill has already cleared Arizona's House of Representatives and is now being debated in the state Senate. Moreover, voters here in November approved four ballot initiatives targeting illegal immigrants. One denies in-state tuition rates to undocumented college students.

By April, 40 other states had introduced 199 bills related to employment of undocumented workers – the top subject of concern in the states. The next is law enforcement, then benefits and, closely behind, education, according to the NCSL.

Stresses in new places

Though the US is a nation of immigrants, and the percentage of new immigrants today may actually be lower than in the late 19th century and early 20th century, the patterns have changed.

"Immigrants are going to places like Hazelton, Pa., or towns in Georgia, Alabama, and Mississippi where the economies are doing better," says Joe Vail, director of the Immigration Law Clinic at the University of Houston.

While these communities have plenty of jobs, they don't have the classrooms and other services to support these immigrants and their families. The costs of education, medical care, and other social services are creating financial burdens on them that aren't reimbursed by the federal government, says Professor Vail.

The NCSL's Ms. Steisel says immigration issues now affect all 50 states. As recently as 10 years ago, she says, only five states – New York, Texas, Florida, Illinois, and California – were dealing with serious immigration problems. She cites North Carolina as an example. The 2000 census showed that the state had recorded a 400 percent increase in foreign-born residents.

"That is an extraordinary number," Steisel says. "What you see now is states that never before had to deal with immigrants now have to figure out how to handle questions as complex as human trafficking, what documents are necessary for employment – a wide set of issues."

Pitfalls of state and local laws

But when states and municipalities tackle these issues, problems can arise. For example, the federal government already requires employers to verify workers' documents, through the Immigration Reform and Control Act of 1986 (IRCA). When local governments take that responsibility on themselves, it only clogs up the system, experts say.

Moreover, putting the onus on landlords to verify a potential tenant's immigration status could cause major problems with monitoring and enforcement, and may lead to discrimination if landlords prove to be unwilling to bear the costs of defending their judgments.

"If a municipality or state has such landlord sanctions in place, we could see discriminatory standards in housing," says Rodolfo Espino, a political scientist at Arizona State University (ASU).

That's what happened in the workplace, he says. "After IRCA, Asians and Hispanics were discriminated against because employers didn't want to take the risk that the paperwork they accepted may be challenged."

Employers chose instead to hire whites, leading to a number of discrimination cases Dr. Espino says. "The spillover effects could be very disastrous."

Pleas for federal action

The pitfalls of immigration law are leading some state and local politicians to plead with the federal government to act.

"I implore lawmakers to go back to the table, iron out their differences, and give us an immigration system that is enforceable, and the resources to enforce it," Arizona Gov. Janet Napolitano wrote in an op-ed that appeared Monday in The Washington Post.

"If there is a solution [to illegal immigration], it would have to come at the federal level," says David Berman, professor emeritus of political science at ASU. "The problem is national and international in nature, something that would be difficult to handle on a state-by-state basis."