Since 1995, unauthorized immigrants have exceeded those with permission to immigrate, according to the Pew Hispanic Center. In 2004, 53 percent of 1.3 million immigrants were illegal. The flow of illegal immigrants peaked in the mid- to late 1990s at about 750,000 a year.

Do illegal immigrants get public aid, such as Medicaid or welfare grants?

Only citizens or legal residents are eligible for food stamps or welfare-to-work programs.

Medicaid, the joint county-state-federal health-care program for the poor, covers only emergency services for illegal immigrants. County departments of social services determine the eligibility for coverage for childbirth. For all other emergency services, the Division of Medical Assistance determines eligibility.

Are hospitals required to serve illegal immigrants?

Federal law requires hospitals to examine and, if warranted, treat all who come to their emergency rooms.

Are public schools required to enroll illegal immigrants?

Federal courts have repeatedly ruled that schools must provide free education to all children, no matter how they got here. Keep in mind that many children of illegal immigrants are born in the United States. That means they're U.S. citizens -- it's in the Constitution.

Illegal immigration is a national problem. Why isn't the federal government cracking down?

U.S. Immigration and Customs Enforcement officials say that their biggest concern is national security and that their resources need to be applied to finding and deporting immigrant felons and illegal workers in sensitive workplaces -- such as nuclear plants or military bases. Cracking down on illegal workers or the employers who hire them is a low priority.

Some lawmakers are trying to shift the burden of proof from the government to employers. Congress is considering a proposal to increase from $250 to $10,000 the fine employers pay for knowingly hiring illegal immigrants. Another proposal would require businesses to check employees' eligibility against a federal terrorism watch list and Social Security database.