This past Monday, President Trump released a new executive order shutting down the refugee program for 120 days and banning immigration from six majority-Muslim countries for 90 days. President Trump attempted to justify these changes by stating in part that:

The Attorney General has reported to me that more than 300 persons who entered the United States as refugees are currently the subjects of counterterrorism investigations by the Federal Bureau of Investigation.

The government has refused to provide any additional details about these cases, but an investigation should not be seen as implying guilt. Almost all FBI terrorism investigations do not end with a terrorism conviction. Indeed, the numbers predict that of these 300 refugee investigations, only 1 will turn into a terrorism conviction and that conviction will not be for planning an attack against the United States. This claim about the FBI investigating refugees has turned out to be a groundless smear in the past, and history has shown that refugees have been less likely than others to commit acts of terrorism against the United States. 

These 300 represent less than 0.009 percent of all refugees admitted since 1975. As the Cato Institute’s recent report found, only 20 refugees from 1975 to 2015 have attempted, planned, or carried out a terrorist attack inside the United States. Only 3 carried out a deadly terrorist attack, and all of those were before 1980. During the 40 years from 1975 to 2015, the annual risk of death by a refugee terrorist to a U.S. resident was 1 in 3.64 billion. This makes them about 1,000 times less likely to kill a U.S. resident in a terrorist attack than other foreign-born people.

Unfortunately, this type of baseless fearmongering about FBI investigations into refugees is not new. The FBI told ABC News in 2013 that it was investigating “dozens” of refugees as terrorists. In the 26 months after the FBI made the claim, the agency arrested and convicted 31 individuals for “terrorism-related” offenses. Of these, a majority were U.S.-born citizens. Another 4 convictions were not even for terrorism offenses. In the end, the Bureau only arrested and put away for terrorism offenses 9 foreign-born residents total after it claimed “dozens” of open cases against refugees specifically. None of these individuals were planning attacks inside the United States.

So how often do FBI national security investigations actually turn into convictions?

According to the New York Times in 2016, the Bureau has averaged “7,000 to 10,000 preliminary or full investigations involving international terrorism annually in recent years.” This appears to contrast with Reuters, which reported this week that the 300 refugee investigations were part of 1,000 “counterterrorism investigations” into persons tied to “Islamic State or individuals inspired by the militant group.” Similarly, FBI Director James Comey said in May 2016 that there were “north of a thousand cases” that they were investigating of U.S. residents radicalized by the Islamic State online.

The best explanation that I see for this difference is that the Comey/​Reuters number refers to a narrower subset of investigations involving the Islamic State and, more importantly, only reflects a snapshot in time. At any particular moment, there may be 1,000 or so investigations open, but there are between 7,000 and 10,000 investigations for the entire year.

This means that very few FBI investigations end in a terrorism conviction. In the 5 years from 2010 to 2014, the entire United States government averaged just 27 terrorism convictions per year. Taking the middle of the 7,000 to 10,000 range for the number of new FBI investigations (8,500) would mean that only about 0.3 percent of all terrorism investigations end in terrorism convictions.* 

If these individuals are involved with terrorism, it is very unlikely that they are attempting to harm the United States as opposed to supporting terror groups abroad. Less than 5 people per year were convicted of terrorism offenses in which they were targeting the United States in the five years from 2010 to 2014. This appears to be true today as well. Director Comey said in May 2016 that his main concern was people seeking to join the Islamic State overseas. This means that only 0.05 percent of all investigations end in the conviction of a person who was attempting terrorism in the United States.

Based on these percentages, we can predict that only 1 in 300 of these investigations will turn into a terrorism conviction and that it will not involve a domestic terror plot.

The FBI should continue to investigate people who it has reason to believe are involved in terrorism, but it is incorrect to assume that an investigation means that the person is guilty of a crime or even likely to be guilty of a crime. It is even more incorrect to jump to the conclusion that they pose a threat to anyone in the United States. The fact remains that refugees are less likely than others to commit acts of terrorism, and these new investigations do not change that fact.

*In the less likely scenario where the FBI opens only 1,000 terrorism investigations annually, 2.7 percent would end in terrorism convictions and 0.5 percent would end with convictions for an offense targeting the U.S. These numbers would predict that of these 300 refugees, only 8 will be convicted of a terrorism offense. Of these, only 1 will have planned an attack targeting people inside the United States.