A Center for Immigration study to be released Monday and obtained in advance by The Daily Caller, found that last year ICE reported nearly 722,000 encounters with illegal or criminal immigrants. But ICE officers filed immigration charges against less than 195,000 aliens.

“According to ICE personnel, the vast gap between the number of encounters reported and the number of aliens put on the path to removal exists because officers are not permitted to file charges against aliens who do not fall into the administration’s narrowly defined criteria for enforcement, regardless of the criminal charges or the circumstances in which the alien was identified,” the report, authored by CIS director of policy studies Jessica Vaughan, reads.

Since June 2011, when the first of the Obama administration’s “prosecutorial discretion” policies were put in place, the report adds, interior ICE arrests have declined by 40 percent.