Big increases in immigration since 1990 have not hurt employment prospects for U.S. workers, says a study released Thursday.
The report comes as Congress and many Americans are debating immigration policy, a big issue in this fall's midterm congressional elections.
The Pew Hispanic Center found no evidence that increases in immigration led to higher unemployment among Americans, said Rakesh Kochhar, who authored the study.
Kochhar said other factors, such as economic growth, played a larger role than immigration in setting the job market for Americans.
The study, however, did not look at whether wages were affected by immigration. Advocates for tighter immigration policies argue that immigrant workers depress wages for American workers, especially those with few skills and little education.
Immigration supporters argue that foreign workers often take jobs that Americans do not want and will not take.
The Pew Hispanic Center is a nonpartisan research organization that does not advocate policy positions. The center studied census data on the increase in immigrants from 1990 to 2000, and from 2000 to 2004, for each state. It matched those figures with state employment rates, unemployment rates and participation in the labor force among native-born Americans.
The U.S. had 28 million immigrants _ legal and illegal _ age 16 and older in 2000, an increase of 61 percent from 1990. By 2004, there were 32 million.
Immigrants tend to be younger and have less education than American workers. The study, however, found "no apparent relationship between the growth of foreign workers with less education and the employment outcome of native workers with the same low level of education."