Kudos to Jason Richwine for his fine shoe-leather work in contacting the PPIC staff and determining that the ethnic incarceration figures provided in their 2006 report Who’s in Prison? were already age-adjusted, which he mentioned in a weekend blog item, The Great Hispanic Crime Debate. I do think that anyone reading the explicit text on pp. 4-5 specifying the ethnic incarceration rates per 100,000 for each ethnicity group would certainly not have gotten that impression. Just as in the case of the BJS reports, we see that professional demographers and statisticians are sometimes a little obscure in their expository language. However, the apparent age-adjustment already embedded in the PPIC California data hardly diminishes the conclusions I was claiming to draw from this very useful report.

As I had repeatedly emphasized in my original article and subsequent analyses, I was seeking an age-adjusted ratio of Hispanic/white incarceration rates across different states based on the limited data provided by the BJS reports, especially Table 2005-14. Since the state-by-state numbers provided in BJS Table 2005-14 were not stratified by age, I was forced to adopt the admittedly crude methodology of normalizing these totals to the relevant high-crime age male population, choosing to explore the different results for age cohorts 18-29, 15-34, and 15-44 in order to provide a range of rough estimates. The resulting age-adjusted national incarceration ratios for Hispanics/whites ranged from 1.13 to 1.31 depending upon the age cohort used, with the ratios in California being very similar.

Now my critics, including Richwine, had claimed that these results were wildly inaccurate, arguing that the official data I’d used from BSJ Table 2005-14 was highly erroneous (since it seemingly conflicted with national aggregated figures in a different BJS table). Therefore, I suggested we examine the PPIC California data, probably our most solid nugget of hard evidence, and compare it with the BJS numbers I had used for California. If the results were similar, this would tend to validate the accuracy of the BJS Table 2005-14 numbers and also support my own (crude) age-adjustment methodology.

It turns out that the age-adjusted Hispanic incarceration ratio from PPIC is approximately 10% higher than the California result I had derived for the 15-44 age cohort. Since PPIC presumably used some different (and probably much more sophisticated) age-adjustment methodology and also had access to far more detailed local demographic and prison data, a 10% difference in final results is hardly surprising. Given all the other vast unknowns, uncertainties, and demographic factors, I have never denied that my overall estimates of apparent Hispanic criminality might easily be off by 10% or 20%.

To the extent that my age-adjusted incarceration estimates have now been calibrated by the hard data from California (using PPIC’s own age-adjustment methodology) and seemingly found to be 10% low, I urge all readers to mentally revise upwards all my other incarceration estimates by that same 10% amount. (As an interesting cultural aside, the PPIC data is gender-stratified, and whereas in California Hispanic males are 48% more likely to be incarcerated that white males, among females the opposite is true, with white females actually being 30% *more* likely to be in prison than Hispanic females; since both my primary BJS data and also my criminality estimates are gender-aggregated, this brings the composite PPIC numbers a bit closer
to my own.)

Whether or not a revision of this size materially affects the central conclusions of my article must be decided by each individual reader. However, I will repeat that anyone who actually looks at the ethnic incarceration graphs from the PPIC report and compares them to the ethnic incarceration graphs found in my own article will notice a very striking similarity in appearance.

We should also remember that the age-adjusted incarceration ratio between whites from Texas or Georgia and whites from New Jersey or Illinois is roughly 300%. Perhaps that helps to provide a useful perspective to the apparent 10% Hispanic underestimate in my own
article.

P.S. I’d also like to mention an amusing aside which illustrates the typical sources of America’s “His-Panic” in the media and on the Internet.

Over the weekend, Randall Parker, a staunch anti-immigrationist who blogs at ParaPundit, posted an item entitled “Santa Barbara Crime Wave?”, calling attention to a headline story in his newspaper on the soaring rates of local violent crime. Now Santa Barbara’s white population is very affluent, but since Hispanics constitute about 40% of both the city and the county and are quite poor, they obviously must represent the source of this “spike in crime.” Therefore, he regarded his local evidence as a powerful refutation of my own article, and emailed me the details, adding a few notes of sarcasm.

Obviously a single data point cannot refute national correlations. But when I actually looked at the “tragic details” described in the Santa Barbara article, I noticed a very curious lack of specific data on homicides and violent crime. I also noticed that a day or two earlier, the newspaper had carried a top story on Santa Barbara’s severe budget crisis and resulting proposals by local elected officials to cut the law enforcement budget. This made me wonder whether the alleged spike in crime was real, or just a propaganda weapons being used in budget negotiations, and I mentioned my doubts to Parker.

Sure enough, once he located the actual crime statistics for his city, he discovered that crime had been completely stable or even declining for the last decade. Overall, 40% Hispanic Santa Barbara has a murder rate about the same as my own 95% white or Asian Palo Alto, and just one-third that of 95% white or Asian Beverly Hills, placing it close to Toyko, Japan. Presumably, if Santa Barbara’s murder rate had actually tripled, pushing it up to that of a notorious urban-hellhole like Beverly Hills, the story would have made the front page of The New York
Times
.

If I hadn’t bothered responding to the email, I have no doubt that excitable anti-immigrationists would have endlessly cited Santa Barbara’s horrific crime wave as further proof of the dreadful social impact of Hispanic immigration…