“The reality is that under this president, since 9/11, this anti-Muslim United States of America has doubled the rate of Muslim immigration. Since 9/11.”

— Former senator Rick Santorum of Pennsylvania, in the GOP debate, Dec. 15, 2015

This statement made at the undercard GOP debate jumped out at The Fact Checker. Is it correct that the rate of Muslim immigration to the United States has doubled since the Sept. 11 attacks?

The Santorum campaign did not respond to repeated requests for comment, but the source of this factoid appears to be an article that appeared in the online publication Conservative Review. But do the numbers really show this?

The Facts

Santorum appeared to pin this figure on President Obama’s policies, but of course George W. Bush was president until 2009. For the purposes of this fact check we will compare immigration from key majority-Muslim countries before and after 9/11.

The Conservative Review article, written by Daniel Horowitz, focused on the number of green cards (legal permanent residence) issued to people from predominantly Muslim countries from 2001 to 2013 — approximately 1.6 million. The article noted that this is an imperfect measure because the immigration service does not track the religion of people who receive green cards, so there may be religious minorities from those countries who make up a large chunk of the immigrants (one example: Coptic Christians fleeing Egypt).

Counting green cards is also imperfect because not all of those people end up staying permanently in the United States. A Department of Homeland Security report found that of 25 million people who obtained LPR status between 1980 and 2009, about 11 million became citizens and 3 million returned home or passed away; 11 million had retained their status but had not naturalized.

We had trouble finding a baseline figure in Horowitz’s article for which to compare the pre-2001 and post-2001 eras. He wrote in an email that he was referring to a report from the Pew Research Center, which he wrote estimated “100,000 new Muslim immigrants a year, almost twice the level of the previous decade.”

Alan Cooperman, director of religious research at Pew, warned that “these are fairly rough estimates,” derived from DHS data and a 2003 survey of new immigrants. The data indicates that in 1992, about five percent of green card holders were Muslim, compared to 10 percent in recent years. (Hindu immigrants also increased, from three percent in 1992 to seven percent.)

But Cooperman noted that while the estimated percentage of Muslims has remained relatively constant, “the overall numbers of immigrants are going up,” he said.

For an unknown reason, Horowitz included 2001 in his post-2001 figures, even though the terrorist attack took place toward the end of the year. To test Santorum’s claim, we used DHS data to compare the average annual immigration from the Muslim-majority countries with the largest number of immigrants in the 10 years before the attacks (1992-2001) with the average annual figure in the 12 years since 2001 (2002-2013).  The results are below.

As you can see, a handful of countries — Iraq, Indonesia and Somalia — experienced a doubling of the rate of green cards being issued. A number of other countries had big gains, but some key Middle Eastern countries (Jordan, Lebanon and Syria) actually saw declines. The two biggest sources of immigrants — Pakistan and Iran — actually had gains that lagged the general immigrant population.

Overall, these Muslim-majority countries had an average increase in green card recipients of 55 percent, compared with 30 percent for all countries. That’s an increase, but it’s not a doubling of the rate.

The Pinocchio Test

Santorum went too far in saying the United States had doubled the rate of Muslim immigrants since the Sept. 11 attacks. The rate has gone up, but so has the rate for all immigrants. In effect, immigration for key Muslim countries is 25 percentage points higher than for the general immigration population.

Moreover, one must remember the caveat that the actual religious affiliation of these green card holders is unknown, making it even more important to not be so categorical.

Two Pinocchios

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