A “backdoor amnesty” for illegal immigrants, or a smarter, more targeted way to keep the nation safe?

That is the question under debate in the US this week, after big news that the Department of Homeland Security (DHS) is shifting its practices to focus deportations on criminals, halting cases of those who are merely in the US illegally.

The Obama administration has been behind record deportations of illegal immigrants: about 400,000 a year for the past three years. But critics have complained that most of them are otherwise law-abiding citizens just trying to improve their lives while backlogs in immigration courts grow.

With new training and a review of cases, announced this summer but beginning now, agents and prosecuting immigration lawyers will be trained to look for cases of undocumented immigrants who are security threats to the US.

According to a DHS statement, the training “will help reduce inefficiencies that delay the removal of criminal aliens and other priority cases by preventing new low-priority cases from clogging the immigration court dockets.”

The New York Times also writes about a review of the some 300,000 cases currently in the system. Cases will be closed for those deemed a low priority, the paper writes, though they will not be dismissed. “Taken together, the review and the training, which will instruct immigration agents on closing deportations that fall outside the department’s priorities, are designed to bring sweeping changes to the immigration courts and to enforcement strategies of field agents nationwide.”

The move was applauded by immigrant rights groups and others. “The American Immigration Lawyers Association (AILA) commends Immigration and Customs Enforcement (ICE) for today’s announcements that the agency will begin its review of certain currently pending cases before the immigration courts, as well as future cases that come before the Offices of Chief Counsel (OCC).”

But it was immediately criticized. Rep. Lamar Smith (R) of Texas, for example, deemed it a "backdoor amnesty.”

Those most likely to benefit from the administration's shift: students who crossed the border under age 16 and are enrolled in college, children who’ve been in the US more than five years, the elderly, and those who have signed up for the military.

Reuters says it could help some 2 million young people residing in the US.