The WikiLeaks organization was criticized for providing a target list for terrorists when it published a secret memo in 2010 with 200 international sites that the U.S. Department of State considered critical to national security.

Was there any truth to that claim?

Dr. Daniel G. Arce, Ashbel Smith Professor and program head of economics in the UT Dallas School of Economic, Political and Policy Sciences, wanted to find out. In a new study published in the International Journal of Critical Infrastructure Protection, he found no evidence that the leak led to any attacks.

"When the list came out, there was a lot of concern that this was a to-do list for terrorists," Arce said. "I wanted to answer the question. If you're going to make claims, at some point you have got to look back and see if the claims were true."

WikiLeaks published a secret memo listing critical infrastructure facilities around the world. The classified Department of Homeland Security information listed weapons manufacturers, mines, pharmaceutical facilities and other sites that, if attacked, would critically impact the United States. U.S. officials denounced WikiLeaks for releasing the list, saying it could jeopardize national security.

As part of his analysis, Arce compared the facilities with more than 40,000 terrorism incidents entered in the Global Terrorism Database, which includes information on terrorism events. Arce focused on events occurring from December 2010 through 2014.

Of more than 200 sites on the State Department's list, two were attacked after the locations were leaked.

An attack on an oil refinery in Basra, Iraq, resulted in no casualties. Arce said it would be difficult to attribute the attack to WikiLeaks given the insurgent activity in that nation. The other attack was on the Baku-Tbilisi-Ceyhan pipeline in Turkey, which had been attacked multiple times before the release of the WikiLeaks list.

"It's really unlikely that it was a to-do list for terrorists," Arce said. "It doesn't appear that it created as much of a security risk as claimed." He noted that failed attacks might not be chronicled in the database.

Although Arce said the leak did not turn out to be a target list for terrorists, the document revealed which sites the U.S. government deemed most critical. Arce's analysis found that those locations differed significantly from targets previously attacked by terrorists. He said the sites may have been included based on anticipated attacks rather than on previous attack patterns.

"It's possible that sites on the list were not attacked because the list prompted better security at those locations," Arce said. "Based on these findings, more research is needed to evaluate the risks to facilities on the list."