By Hans Johnson, research fellow, Public Policy Institute of California
This opinion article appeared in the North County Times on March 18, 2007

At the Public Policy Institute of California, we recently published an economic analysis by Giovanni Peri of UC Davis looking at how immigrants affect the jobs and wages of U.S.-born workers in California. The study uses the most reliable and representative data available – the decennial Censuses and the American Community Survey. It also goes beyond most previous research by using methods that more accurately measure how immigrants and U.S.-born workers interact in the labor market.

Under this microscope, the claim that immigrants take jobs and lower wages of U.S.-born workers, on average, simply doesn't hold in California.

Response to the report has been heated. It demonstrates once again that the passion fueling the nation's immigration debate leads people to discount, ignore – or even flatly deny – empirical evidence. That's unfortunate because it makes an already divisive and complex issue even more volatile, erratic and difficult to address.

Much of the debate and previous research has assumed that immigrants and U.S.-born workers, of the same age and education, compete for the same jobs. Two findings in our study provide strong evidence against this assumption.

First, from 1960 to 2004, the data shows no link between the large number of immigrants moving into California and U.S.-born workers either moving out of the state or dropping out of the work force. In other words, on average, U.S.-born workers were not displaced because of immigrants moving into the state.

Second, between 1990 and 2004, the real wages of U.S.-born workers received a positive boost – an estimated 3 to 5 percent – from the presence of immigrants in the work force. The amount that wages increased varied, depending on age and education, but almost without exception, the results were positive for U.S.-born workers.

The study reveals that immigrants do not compete directly with the majority of U.S.-born workers for the same jobs. Rather, they complement U.S. workers in terms of skills, education and occupations.

For example, in the agricultural field, most immigrants have taken jobs as agricultural laborers, while most U.S. workers have filled jobs such as farm supervisors. As the ranks of one type of worker increase, so does the demand for this other, complementary type.

In a sense, what California workers have done is "upgrade" themselves, taking advantage of opportunities created by newly arrived workers to the labor force.

The data includes legal and illegal immigrants. The U.S. censuses do not collect information on legal status. No large-scale, reliable survey does. This is why no one is able to draw exact conclusions about the different effects of legal and illegal immigrants.

A complex set of priorities and issues drives the national debate on immigration. Our report does not draw, or attempt to draw, any conclusions about broader issues, such as homeland security. What it does do is add to mounting empirical evidence contradicting the theory that immigrants weaken employment opportunities for U.S.-born workers.

Resolving questions, debunking inaccuracies and dealing in facts should be the way to developing sound and pragmatic immigration policy.