They work on farms, at construction sites and in office buildings. They attend public schools, get treated at hospitals and receive help from police officers and firefighters. In some cases, they pay taxes; in others, they don't.
Illegal immigrants are deeply entrenched in the U.S. economy. But what's greater: the amount they contribute or the amount they cost?
A reader's curiosity about illegal immigrants and the economy inspired a questions in this edition of "Ask AP," a weekly Q&A column where AP journalists respond to readers' questions about the news.
If you have your own news-related question that you'd like to see answered by an AP reporter or editor, send it to newsquestions(at)ap.org, with "Ask AP" in the subject line. And please include your full name and hometown so they can be published with your question.
Q: I hear so many conflicting stories on illegal immigration. Please tell me if you can how much the illegal immigrants contribute to the economy and how much they use in free services. If they all got deported, how would it affect our economy?
A: It's tough to say how many people are in the U.S. illegally, let alone how many are working or using public resources. Every study uses rough estimates. Still, we do have some clues.
Illegal immigrants contribute to the economy whenever they pay sales tax and, indirectly through rent payments, real estate taxes.
Also, those who use false Social Security numbers pay taxes into the system they don't get back, since people here illegally aren't eligible to receive Social Security payments. In 2003 alone, the government received Social Security taxes on $57.8 billion from wage reports that couldn't be matched to the person filing.
Illegal immigrants are excluded from most federal and state entitlements like subsidized housing or food stamps, and a 2007 congressional report found they appear to contribute more than they use in services. But the money they contribute often goes to federal and state coffers, while many services they benefit from, such as health and law enforcement, come out of local government budgets.
Several studies show more than half of the country's estimated 12 million illegal immigrants are uninsured (out of a total of 47 million uninsured people in the U.S.) and thus likely to use public emergency rooms that treat everyone regardless of ability to pay. It's difficult to calculate the amount of free health care or, for that matter, free public-school education they benefit from, since it simply isn't known what proportion of these services go to people who are in the country illegally.
Another cost of illegal immigrants: Their willingness to accept low wages drives down wages in some industries. Then again, if immigrants didn't take these jobs, some of them might get outsourced overseas.
Using Pew Hispanic Center and U.S. Census statistics, the independent economic research firm the Perryman Group concluded that if all illegal immigrants were deported, agriculture would lose nearly a quarter of its workers, the building maintenance industry would lose 17 percent and the construction industry would lose almost 15 percent.
Laura Wides-Munoz, Miami
Jacques Billeaud, Phoenix
Suzanne Gamboa, Washington
Associated Press Writers