What is the methodology that produced the numbers quoted in that "study"? How can they possibly estimate the impact of an sample group whose absolute size is unknown?
Quote from the article.. BTW.. it was an FR thread...
A new study from the Center for Immigration Studies is one of the first to estimate the impact of illegal immigration on the federal budget. Based on Census Bureau data, the study estimates that households headed by illegal aliens used $10 billion more in government services than they paid in taxes in 2002. These figures are only for the federal government; costs at the state and local level are also likely to be significant. The study also finds that if illegals were given amnesty, the fiscal deficit at the federal level would grow to nearly $29 billion.
Notice that if you calculated in the state level expenses that 10 billion would be far higher. So the article I posted is a conservative guess. Being that it was an government study, you can bet they didn't show the true extent of the problem.