The Obama administration is threatening public safety by deliberately hampering immigration law and releasing aliens with criminal records, according to a new review of internal Immigration and Customs Enforcement data.

A Center for Immigration Studies report 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.

“The Obama administration and anti-enforcement activist groups have tried to portray the number of departures as ‘record-breaking’ and indicative of robust immigration enforcement. They have tried to support this claim by showing that the number of departures credited to ICE is higher than ever before,” the report reads. “However, an independent analysis of ICE records obtained in a lawsuit showed that ICE was able to achieve these ‘record’ departures only because the agency was taking credit for removing a large number of individuals who were apprehended by the Border Patrol. Such cases made up the majority of ICE’s reported deportations in 2013, but they had never been counted that way in previous administrations.”

Indeed, as the review highlights, many aliens with criminal convictions have simply been released.

In 2013 some 68,000 criminal aliens were released — or 35 percent of all criminal aliens ICE reported encountering, according to the report. ICE field offices with the highest rates of criminal releases were San Antonio (79 percent), New York City (71 percent), Washington, D.C. area (64 percent), and Newark, N.J. (60 percent).

“These figures suggest that despite claims of a focus on public safety, the administration’s prosecutorial discretion criteria are allowing factors such as family relationships, political considerations, or attention from advocacy groups to trump criminal convictions as a factor leading to deportation,” the report reads.

The data is sure to further frustrate critics of the Obama administration’s immigration policies that much more, including Alabama Republican Sen. Jeff Sessions who says the “[Department of Homeland Security] is a department in crisis” and is calling on DHS Sec. Jeh Johnson to “reject the President’s demands to weaken enforcement further and tell him that his duty, and his officers’ duty, is to enforce the law – not break it.”

“As Homeland Secretary, Mr. Johnson is tasked with ensuring the public safety and the rule of law. But Secretary Johnson is not meeting these duties,” Sessions said in a statement to TheDC. “American citizens have a legal and moral right to the protections our immigration laws afford — at the border, the interior and the workplace. The administration has stripped these protections and adopted a government policy that encourages new arrivals to enter illegally or overstay visas by advertising immunity from future enforcement.”

“Comments from top Administration officials, such as Attorney General Holder’s claim that amnesty is a civil right, or Vice President Biden’s claim that those here illegally are all U.S. citizens (apparently including someone whose visa expired yesterday), demonstrate the administration’s increasing belief in an open borders policy the American public has always rejected,” he added.

According to Vaughan, Congress should initiate an official look into the impact of the administration’s prosecutorial discretion policies.

“The Obama administration’s deliberate obstruction of immigration enforcement, in which tens of thousands of criminal aliens are released instead of removed, is threatening the well-being of American communities,” she said.

To Sessions, however, it is Republicans who must work to hold the administration accountable for its rejection of the law.

“The Administration’s lawless policies have not only impaired public safety but increased economic suffering for millions of vulnerable Americans by depriving them of their jobs and wages,” he said. “Unfortunately, Congressional Democrats continue to empower this lawlessness. Republicans must work to end it.”

Other key findings in the review include:

In 2013, ICE charged only 195,000, or 25 percent, out of 722,000 potentially deportable aliens they encountered. Most of these aliens came to ICE’s attention after incarceration for a local arrest.

ICE released 68,000 criminal aliens in 2013, or 35 percent of the criminal aliens encountered by officers. The vast majority of these releases occurred because of the Obama administration’s prosecutorial discretion policies, not because the aliens were not deportable.

ICE targeted 28 percent fewer aliens for deportation from the interior in 2013 than in 2012, despite sustained high numbers of encounters in the Criminal Alien and Secure Communities programs.

Every ICE field office but one reported a decline in interior enforcement activity.

ICE reports that there are more than 870,000 aliens on its docket who have been ordered removed, but who remain in defiance of the law.

Under current policies, an alien’s family relationships, political considerations, attention from advocacy groups, and other factors not related to public safety can trump even serious criminal convictions and result in the termination of a deportation case.

Less than 2 percent of ICE’s caseload was in detention at the end of fiscal year 2013. About three-fourths of the aliens ICE detained in 2013 had criminal and/or immigration convictions so serious that the detention was required by statute.

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