Updated

State lawmakers are increasingly stepping into the void created by the failure of Congress to approve sweeping changes to immigration policy, a new report finds.

Legislatures have passed bills dealing with a range of immigration issues, from employment and health care to driver's licenses and human trafficking — creating a sometimes uneven patchwork quilt of immigration law across the country.

Arkansas approved a law barring state agencies from contracting with businesses that hire illegal immigrants. Louisiana has a new law barring the state from issuing driver's licenses to foreigners until their criminal background has been checked. Oregon made it illegal for anyone other than lawyers to perform immigration consultation work.

In the first six months of the year, 171 immigration bills became law in 41 states. That's more than double the 84 laws approved in all of 2006, according to the report by the National Conference of State Legislatures, being released Monday at the group's annual meeting in Boston.

More than half of the states have considered bills seeking to toughen or clarify laws related to driver's licenses or other identification. Nineteen have studied immigration laws that would affect the ability of immigrants to find jobs.

While the states have been taking action, Congress failed this summer to pass President Bush's immigration plan, which would have legalized as many as 12 million unlawful immigrants while fortifying the border.

Though immigration previously was largely a concern of border states, it has quickly become a national concern, and lawmakers in all 50 states are weighing legislation this year, according to Sheri Steisel, NCSL immigration policy director.

"Given the absence of federal consensus of national immigration reform, state legislators are stepping into the void and doing their best," Steisel said. "They can't wait. They have to deal with the reality of how immigrants impact their communities now."

However, their newly enacted policies don't always agree, she said.

While Arizona lawmakers passed a bill requiring employers to use a new federal database to avoid hiring illegal immigrants, lawmakers in Illinois passed a bill barring businesses from using the same database, saying it contained too many errors.

"We have states looking at same problem and coming up with different solutions," she said.

In any event, state lawmakers have little choice but to step into the immigration fray, said Leticia Van de Putte, a state senator from Texas and NCSL president.

"This is that one glaring issue that continues to tax our state budgets because of the lack of comprehensive immigration reform at the federal level," she said.

A top issue in her home state is human trafficking. One of the nation's main trafficking routes runs through San Antonio and Houston, and a new law set to take effect in September in Texas increases penalties and creates a more exact definition of human trafficking.

Immigrant rights advocates say that while some of the legislation is welcome, they fear some legislators will overreact.

"The downside is that so many states will pass so many different kinds of bills that we will find ourselves in the middle of an unworkable patchwork of laws, many of which will be found unconstitutional," said Rich Stolz, director of the Fair Immigration Reform Movement, based in Washington, D.C.

The result isn't always pretty when states step in on issues with national implications, said Julian Zelizer, professor of history and public affairs at Princeton University.

"You get a much more haphazard response. It's a much messier solution," he said.