Natpolitano, who is leaving the Obama administration Sept. 6 to become chancellor of the University of California system, pointed the finger at Congress for failing to pass the DREAM Act to provide a path to citizenship for children brought to the country illegally by their parents.

“We instructed our immigration agents and officers to use their discretion under current law to not pursue low-priority immigration cases, like children brought to the United States illegally by their parents,” she said at a National Press Club speech. “Congress had a chance to give these so-called Dreamers a way to stay in our country through the DREAM Act, but unfortunately, that legislation failed to garner the 60 votes needed for cloture, falling just five votes short, despite strong bipartisan support.”

Napolitano said she used her “prosecutorial discretion” to allow Dreamers to obtain legal status to stay in the country and said more than 80 percent of the 500,000 requests for deferred action have been approved in the program’s first year.