Conservative arguments against immigration reform took another blow yesterday with the release of a new study about immigrant contributions to the federal safety net. According to a new study published in the journal Health Affairs, immigrant communities contribute billions more to the Medicare Trust Fund than they use. And since the opposite is true of the U.S. born, immigrants are paying for everyone’s grandmother’s healthcare. According to the data, this will remain true for decades to come.

The new findings should come as a bit of an embarrassment to fiscal conservatives who are threatening to hold up or derail the immigration overhaul over stated concerns about health care costs. The L.A. Times reported last week that Republicans in the House hoped to include language in an immigration bill that would lead to the deportation of immigrants who failed to pay hospital bills. The new data makes quite clear that immigrants are already paying those bills, and some.

The article in Health Affairs figures expenditures from naturalized, documented and undocumented immigrants left nearly $14 billion in Medicare Trust Fund surplus in 2009. That’s in contrast to $31 billion in deficit from U.S. born people who paid in less than they used. Between 2002 and 2009, immigrants produced $115 in Trust Fund surplus.

This surplus is mostly because immigrants tend to be younger, working age adults who contribute more than their share to payroll taxes.

“Most of the surplus from immigrants was contributed by noncitizens and was a result of the high proportion of working-age taxpayers in this group,” the from Harvard and The City University of New York researchers wrote.

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