Story highlights Napolitano is now the president of the University of California system

She says there are about 4,000 undocumented students in the system

Washington (CNN) Former Department of Homeland Security Secretary Janet Napolitano explained Thursday that she is suing the Trump administration over its decision to rescind a program to protect young undocumented immigrants because "these young people are really caught between a rock and a hard place."

"They were brought to the United States as young children," she told CNN's Chris Cuomo on "New Day." "We sued the Trump administration for repealing the policy because we contend that the administration violated the administrative procedures act and the due process clause of the Constitution. And we seek to vindicate those rights in the court."

Napolitano, who served under President Barack Obama, is now the president of the University of California system and said there are at least 4,000 undocumented students in the system, with the majority under the Deferred Action for Childhood Arrivals program, or DACA. She was in charge of DHS when DACA was established in 2012.

On Tuesday, a federal judge ordered the Trump administration to reveal internal deliberative documents that went into the decision to rescind the DACA program, a partial victory for groups challenging the rescission in a California federal court.

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