The rate at which police departments are holding undocumented immigrants being targeted for deportation by the Department of Homeland Security has fallen by 30 percent in recent months, says a report by the Transactional Records Access Clearinghouse (TRAC), an independent research organization at Syracuse University. The downturn is part of a trend of rapidly declining requests in recent years.

Homeland Security's system, known as the Secure Communities program, is a tool that allows Immigration and Customs Enforcement (ICE) to ask local, state and federal law enforcement agencies to hold suspected noncitizen criminals in order to give ICE an opportunity to take them into custody and remove them from the country.

Advocate groups said the system did not target serious criminals and was responsible for breaking up families and destroying communities. Those held are known by ICE as "detainers." 

“The decline in the use of detainers does parallel a period of growing criticism of the Secure Communities program by state and local law enforcement agencies, immigration rights groups, and others,” the report said.

The number of those detained by the program peaked in March 2011, when police were holding nearly 28,000 people. In contrast, the figure five years earlier was just a few hundred, while April’s figures, the most recent available, stood at just under 8,000.

A November 2014 Homeland Security memorandum formally ended the Secure Communities program and replaced it with a less aggressive initiative known as the Priority Enforcement Program.

The agency now determines detention requests for immigrants “on a case-by-case basis with a priority for detention of serious criminal offenders and other individuals who pose a significant threat to public safety,” said Jennifer Elzea, an ICE spokeswoman.

She added that ICE “is focused on smart, effective immigration enforcement that prioritizes the removal of criminal aliens, recent border crossers and egregious immigration law violators, such as those who have been previously removed from the United States.”