I have no doubt that in areas with high concentrations of illegal aliens, they're more likely to make up a majority of uninsured hospital visits. Similarly, increased crime wouldn't be unexpected. But I'd be very surprised if those things could be generalized to the whole of southern California or to the whole of government services.
The Tony Dolz article you found cites the Center for Immigration Studies for his $10B cost to the Federal government in services to illegals. The relevant paper there seems to be [link|http://www.cis.org/articles/2004/fiscal.html|The High Cost of Cheap Labor]. Among other [link|http://www.cis.org/articles/2004/fiscalmethods.html#Data|assumptions] it uses are:
Data Source. This report relies on the March 2003 Current Population Survey (CPS) collected by the U.S. Census Bureau. The March data, also called the Annual Social and Economic Supplement, includes an extra-large sample of minorities and is considered one of the best sources of information on the foreign-born.4 The foreign-born are defined as persons living in the United States who were not U.S. citizens at birth.5 For the purposes of this report, foreign-born and immigrant are used synonymously. The Survey includes most legal immigrants and is thought to capture roughly 90 percent of the illegal alien population. We use the term illegal alien or illegal immigrant to mean those who responded to the survey who are in the United States without authorization. All other foreign-born persons are referred to as legal immigrants, including those with Permanent Residence, those who are naturalized American citizens, and those living in the United States on long-term temporary visas, mainly guest workers and foreign students.
[...]
Identifying Illegal Aliens. The CPS does not ask the foreign-born if they are legal residents of the United States. However, the Urban Institute, the former INS, and the Census Bureau have used socio-demographic characteristics in the data to estimate the size of the illegal population. To determine who are legal and illegal immigrants in the survey, this report uses citizenship status, year of arrival in the United States, age, country of birth, educational attainment, sex, receipt of welfare programs, receipt of Social Security, veteran status, and marital status. We use these variables to assign probabilities to each respondent. Those individuals who have a cumulative probability of one or higher are assumed to be illegal aliens. The probabilities are assigned so that both the total number of illegal aliens and the characteristics of the illegal population closely match other research in the field, particularly the estimates developed by the Urban Institute.
This method is based on some well-established facts about the characteristics of the illegal population. For example, it is well known that illegals are disproportionately male, unmarried, under age 40, have few years of schooling, etc. Thus, we assign probabilities to these and other factors in order to select the likely illegal population. In some cases we assume that there is no probability that an individual is an illegal alien. If an individual reports that he is U.S.-born or a naturalized citizen of the United States, then he is assumed not to be an illegal alien. Someone who reports that he is veteran or receives veteran benefits is also assumed not to be an illegal alien. Those individuals who report that they personally receive Social Security benefits, cash assistance under Temporary Assistance to Needy Families (TANF), Supplemental Security benefits (SSI), or who are enrolled in Medicaid are also assumed not to be illegal aliens. However, other members of a household headed by an illegal alien can receive these programs, mostly the U.S.-born children of illegals. It is worth noting that our findings show that only a tiny fraction of households headed by illegals receive cash welfare programs or Social Security benefits. However, a large share of children in illegal alien households use the school lunch program or are enrolled in Medicaid. Our methodology allows for such a possibility.
We estimate that there were 8.7 million illegal aliens in the March 2003 CPS. It must be remembered that this estimate only includes illegal aliens captured by the March CPS, not those missed by the survey.10 By design this estimate is very similar to those prepared by the Census Bureau, the former Immigration and Naturalization Service (INS), and the Urban Institute.11 Although it should be obvious that there is no definitive means of determining whether a respondent in the survey is an illegal alien, the findings in this study are consistent with previous research. For example, the Urban Institute estimated that in 2002 Mexicans accounted for 57 percent of the illegal population; our method finds 58 percent in 2003. Using 2003 data, we estimate that 88 percent of illegals arrived after 1990; the Urban Institute estimated 85 percent using 2002 data.12 Our results also produce estimates that are similar in other areas, such as age and workforce participation.
[...]
And these figures are for all immigrants, not specially for the one-fourth of the foreign-born who are illegal aliens.
Emphasis added.
They think the CPS gets 90% of illegal aliens, bringing the total to 9.7 M by March 2003. Assuming an increase of 500k per year (as another article I skimmed claims) would give 11 M in March 2006. That's in the same range bandied about recently - but it's still just an estimate (with unknown error bars). But note that they massage their estimates to get them to agree with other estimates. We don't know if any of them are any good from the information available.
If they know that illegal immigrants are disproportinately single men under 40, they wouldn't be putting much stress on the school system or the hospitals (compared to familes with young children or the sick, frail and elderly), would they?
At least in this paper, I would have to say that it's built on a house of cards. They don't know how many illegals there are, they don't know how much they're using in public services, and they don't know how similar illegal immigrants are to the estimated 3/4 of the foreign born who are legal immigrants. Hopitals and police departments can certainly have an idea of how illegals are using their services. But I don't think that can be translated to similar usage in other government services.
Illegal immigration is a problem that needs to be addressed. But I don't think this article is better than guesswork at this point. Throwing $10B numbers around is just scaremongering, IMHO.
My $0.02.
Cheers,
Scott.