The Washington Post quoted the research director of the anti-immigrant Center for Immigration Studies (CIS) arguing that immigrants are a drain on public services without noting that the center's analysis on the issue has been criticized as flawed. A study by the libertarian Cato Institute found that immigrants are actually less likely to rely on public benefits than native-born Americans.

In an article examining the effect immigrants have on Social Security, the Post noted that many undocumented immigrants file tax returns and thus pay into the Social Security trust fund, even though they may never be able to access it themselves because they are legally unable to do so. As a counterpoint, the article then included the views of CIS' Steven Camarota:

But Steven Camarota, director of research at the Center for Immigration Studies, which supports limits on immigration, said that America's immigrants are not young or fecund enough to shore up the system.

“If the immigrants all came at 20 and had seven or eight kids, you would see more of a difference,” he said. The average immigrant arrives at age 30, and immigrant women have, on average, 2.1 children, according to the Pew Research Center.

Camarota added that immigrants tend to be poorer than native-born Americans and are therefore more reliant on a wide range of public services. “If you bring in a lot of immigrants who are paying into Social Security but then need all these other social programs -- well, then you're not helping the situation.”

Analysts on both sides agree that increasing the number of highly skilled immigrants would shore up the system more than the Social Security Administration report accounts for, since high-skilled immigrants pay more taxes and spend more than low-skilled ones.

However, in a study released in February, the Cato Institute found that immigrants are less likely than native-born Americans to use public services:

[L]ow-income non-citizen immigrants, including adults and children, are generally less likely to receive public benefits than those who are native-born. Moreover, when non-citizen immigrants receive benefits, the value of benefits they receive is usually lower than the value of benefits received by those born in the United States. The combination of lower average utilization and smaller average benefits indicates that the overall cost of public benefits is substantially less for low-income non-citizen immigrants than for comparable native-born adults and children.

Cato also noted that while immigrants' earnings tend to be lower than Americans' when beginning their careers, that changes over time as they invest more in education and training: "[W]hile immigrants begin with lower earnings, their incomes improve as they remain in the United States for longer periods. As immigrants remain longer in the United States, their English proficiency and other job skills improve, which heightens their earning potential."

After Camarota responded critically to the study's findings in February, Cato pointed out the flaws in CIS' research methodology and concluded that CIS inflated its conclusions that immigrants are a drain on public services by using a “bad approach”:

Our approach is to count the benefits used by immigrants individually while Camarota's approach is to include everyone in a so-called immigrant-headed household regardless of citizenship status - especially U.S.-born children and spouses. 

[...]

In other words, counting the cost of the children of immigrants who are born citizens is a bad approach.  If we were to follow Camarota's methodology, why not count the welfare costs of the great-grandchildren of immigrants who use welfare or public schools today?  Our study, on the other hand, measures the welfare cost of non-naturalized immigrants and, where possible, naturalized Americans.

A 2012 Cato study  arrived at similar conclusions, finding that immigrants tend to settle in states with the lowest spending on public services -- which runs counter to the notion that they are primarily concerned with coming to the United States to use public benefits:

The 10 states with the largest percentage increase in foreign-born population between 2000 and 2009 spent far less on public assistance per capita in 2009 compared to the 10 states with the slowest-growing foreign-born populations -- $35 vs. $166. In the 10 states with the lowest per capita spending on public assistance, the immigrant population grew 31 percent between 2000 and 2009; in the 10 states with the highest per capita spending on public assistance, the foreign-born population grew 13 percent.

If immigrants were primarily concerned with collecting welfare, they would not be flocking to such states as Kentucky, Tennessee, North Carolina, South Carolina, and Georgia. Instead, they would be drawn to such states as Michigan, Rhode Island, and Vermont, which in fact have seen very slow growth in their immigrant populations.

Numerous other studies have also found that immigrants are less likely to use public benefits.

CIS -- a nativist organization whose affiliation with hate groups has been thoroughly documented by the Southern Poverty Law Center (SPLC) -- has repeatedly been criticized for its shoddy research work. In November 2012, the Economic Policy Institute caught the organization cherry-picking economic data to “imply -- misleadingly -- that Obama's policies have favored immigrants over natives and caused disproportionate employment gains for immigrants,” as EPI Vice President Ross Eisenbrey wrote at the time. 

SPLC has stated that CIS often reaches baseless conclusions that are “either false or virtually without any supporting evidence” and the Center for New Community has warned professional journalists that CIS is not a “credible voice in the debate on immigration.”