The three university-affiliated researchers say that the previous estimate of 11.3 million illegals is based on one study with problematic methodology. The researchers took an entirely different approach and came up with the shocking number of 22 million.

However big you thought the problem of illegal aliens in America was, a trio of Yale researches says it's double what everyone thinks.

National Review:

“Our original idea was just to do a sanity check on the existing number,” said one of the study’s authors, Edward Kaplan, a professor of operations research at the Yale School of Management. “Instead of a number which was smaller, we got a number that was 50 percent higher. That caused us to scratch our heads.” “There’s a number that everybody quotes, but when you actually dig down and say, ‘What is it based on?’ You find it’s based on one very specific survey and possibly an approach that has some difficulties. So we went in and just took a very different approach,” said another of the study’s authors, Jonathan Feinstein, a professor of Economics and Management. To arrive at their estimate, the authors used operational data such as deportations and visa overstays as well as demographic data such as death rates and immigration rates. “We combined these data using a demographic model that follows a very simple logic,” Kaplan said. “The population today is equal to the initial population plus everyone who came in minus everyone who went out. It’s that simple.” “The analysis we’ve done can be thought of as estimating the size of a hidden population,” he added. “People who are undocumented immigrants are not walking around with labels on their foreheads. . . . There are very few numbers we can point to and say, ‘This is carved in stone.'” The researchers said their goal in crunching the numbers was not a political one. “We wouldn’t want people to walk away from this research thinking that suddenly there’s a large influx happening now,” Feinstein commented. “It’s really something that happened in the past and maybe was not properly counted or documented.”

The study's data covers a 26 year period from 1990 to 2016. And while the methodology sounds interesting, it's very hard to say how accurate the data is.

But I think it's a safe bet that the 11.3 million illegal alien figure is wrong. Twenty two million sounds very high given what we know about the strain on our welfare, health care, and public education systems already. It's bad, but double the number of illegals would almost certainly be noticeable in public spending - unless the illegals are so far underground they don't use any public systems. If that were the case, how do you count them?

Many researchers always used the caveat "at least" 11.3 million illegals in the US. Now we're pretty sure it's much higher than that.

There has been very little critical commentary on the study, which isn't surprising given that it was just published on Friday. The bottom line is that decades of neglect, non-existent enforcement, and the deliberate application of policies that make entering the country illegally attractive and lucrative have resulted in a dilution of the value of US citizenship.