A story published by The Hill last month about two studies claiming that “immigrants commit less crime than U.S. born citizens” misses the point that President Trump and other Americans are concerned over the crimes committed by illegal aliens, not legal immigrants. And the existing records on those crimes, like the murder of Kate Steinle in San Francisco in 2015, are truly shocking.

Ronald Mortensen points out some of the methodological problems with these studies in his recent piece in The Hill. But the problems are even worse. The Cato study concluded that “legal and illegal immigrants are less likely to be incarcerated than natives” and the Sentencing Project concluded in their report that “foreign-born residents of the United States commit crime less often than native-born citizens.”

But the issue isn’t non-citizens who are in this country legally, and who must abide by the law to avoid having their visas revoked or their application for citizenship refused. The real issue is the crimes committed by illegal aliens. And in that context, the claim is quite misleading, because both of these studies combine the crime rates of both citizens and non-citizens, legal and illegal.

Instead of using official crime data, these reports also use surveys. The Sentencing Project measures "crime and related behavior based on self-reported accounts of behavior" and Cato uses the United States Census American Community Survey (ACS). For obvious reasons, there is little incentive for anyone, let alone criminal aliens, to self-report their crimes. Many respondents will likely also fail to disclose that they are not a citizen out of fear of discovery and deportation.

These studies overlook disturbing actual data on crimes committed by criminal aliens. For example, the Government Accountability Office released two unsettling reports in 2005 on criminal aliens who are in prison for committing crimes in the United States, and issued an updated report in 2011.

The first report found that criminal aliens, both legal and illegal, make up 27 percent of all federal prisoners. Yet non-citizens are only about nine percent of the nation’s adult population. Thus, judging by the numbers in federal prisons alone, non-citizens commit federal crimes at three times the rate of citizens.

The findings in the second report are even more disturbing. It reviewed the criminal histories of 55,322 aliens in federal or state prisons and local jails who “entered the country illegally.” Those illegal aliens were arrested 459,614 times, an average of 8.3 arrests per illegal alien, and committed almost 700,000 criminal offenses, an average of roughly 12.7 offenses per illegal alien.

The 2011 GAO report is more of the same. The criminal histories of 251,000 criminal aliens showed that they had committed close to three million criminal offenses. Sixty-eight percent of those in federal prison and 66 percent of those in state prisons were from Mexico. Their offenses ranged from homicide and kidnapping to drugs, rape, burglary, and larceny.

Once again, these statistics are not fully representative of crimes committed by illegal aliens — this report only reflects the criminal histories of aliens who were in prison. If there were a way to include all crimes committed by criminal aliens, the numbers would likely be higher since prosecutors often drop criminal charges against an illegal alien if immigration authorities will deport the alien.

The GAO reports also highlight another flaw in using survey data from a national sample. A key factor highlighted in the GAO reports is that criminal aliens from Mexico disproportionately make up incarcerations and that most arrests are made in the three border states of California, Texas, and Arizona.

In sum, it has not been proven that illegal aliens commit crimes at a lesser rate than either native-born or naturalized American citizens. In fact, existing data may support the opposite conclusion.

But even if it were true, it would be irrelevant to the point being made by President Trump — that none of the millions of crimes committed by illegal aliens would occur if they were not in the country in the first place or were deported when they were caught instead of being turned loose to repeatedly prey on other victims. That is a simple truth that too many American families know from personal experience.

Republished from The Heritage Foundation.