The comprehensive immigration overhaul being taken up in the Senate this week could cost taxpayers $6.3 trillion if 11 million illegal immigrants are granted legal status, according to a long-awaited estimate by the conservative Heritage Foundation.
The cost would arise from illegal immigrants tapping into the government's vast network of benefits and services, many of which are currently unavailable to them. This includes everything from standard benefits like Social Security and Medicare to dozens of welfare programs ranging from housing assistance to food stamps.
The report was obtained in advance by Fox News.
"No matter how you slice it, amnesty will add a tremendous amount of pressure on America's already strained public purse," Robert Rector, the Heritage scholar who prepared the report, said in a statement.
The study is already coming under criticism from some groups and economists who challenge its assumptions, claiming the legalization would help fuel economic growth. Heritage Foundation President Jim DeMint, though, defended the study ahead of its release Monday morning.
"There's no way you can look at this and say that it's good for the American taxpayer," he told Fox News.
The numbers could raise additional concerns for Republicans as a Senate committee prepares to consider the legislation later this week.
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