U.S. Immigration and Customs Enforcement rarely makes use of prosecutorial discretion to close immigration cases, the Transactional Records Access Clearinghouse said Thursday).

ICE invoked prosecutorial discretion in only 6.7 percent of cases between October 2012 and March 2014, according to TRAC's analysis of official statistics.

A June 2011 policy directive instructed ICE agents to concentrate enforcement efforts on undocumented immigrants who have criminal records or otherwise pose a threat to national security or public safety, while using prosecutorial discretion, or PD, to close cases involving other categories of migrants.

"Overall PD usage has hovered in the 6 to 8 percent range for months, though its use varies widely by location," TRAC, which is based at Syracuse University, said in its report.

At immigration courts in San Antonio, Las Vegas and Newark, New Jersey, ICE has used this criterion in a range of 3-4 percent of cases, while the level drops below 3 percent in the immigration courts of Houston, Buffalo and El Paso, Texas.

Other immigration courts, like those of Tucson and Seattle, have seen a PD closure rate of 30 percent over the past 18 months, according to the report.

On various occasions in the course of many years, the Supreme court has recognized that the decision of a government agency either not to proceed or not to enforce the law, either by means of a civil or criminal suit, is a decision to be taken at the absolute discretion of the agency.

Due to immigration reform being blocked in the House of Representatives, President Barack Obama made a commitment to getting immigration law applied in a "more human" way.

Since President Obama entered the White House in January 2009, the average annual number of deportations up to fiscal year 2013 (last Sept. 30) was 400,000, double the 200,000 in 2007, the highest number during the two terms of President George W. Bush.

Pro-immigrant organizations estimate that the number of deportations was more than 2 million under Obama. EFE