WASHINGTON & SANTA FE, NM (By Robert Pear, NYT) August 18, 2011 — The Obama administration announced on Thursday that it would generally not deport or expel illegal immigrants who had come to the United States as young children and graduated from high school or served in the armed forces.

White House and immigration officials said they would exercise “prosecutorial discretion” to allow these people to stay in the country while the government focused its enforcement efforts on higher-priority cases involving criminals and people who had flagrantly violated immigration laws.

President Obama is, in effect, doing administratively what he could not persuade Congress to do — allowing the secretary of Homeland Security to provide relief to a select group of students who are here illegally but show great promise.

Senator Richard J. Durbin of Illinois, the No. 2 Senate Democrat, has argued for a decade that “these young people should not be punished for their parents’ mistakes.”

White House officials emphasized that they were not granting relief to a whole class of people, but would review cases one by one, using new standards meant to distinguish between low- and high-priority cases.

“The president has said on numerous occasions that it makes no sense to expend our enforcement resources on low-priority cases, such as individuals” who were brought to this country as young children and know no other home, the secretary of homeland security, Janet Napolitano, said in a letter to Mr. Durbin.

Ms. Napolitano said that low-priority cases were “clogging immigration court dockets and diverting enforcement resources away from individuals who pose a threat to public safety.”

Mr. Durbin said he believed the new policy would halt the deportation of most people who would qualify for relief under a bill, known as the Dream Act, that he has repeatedly introduced in the last 10 years.

Under the new policy, the government will review 300,000 cases of people in deportation proceedings to identify those who might qualify for relief and those who should be expelled as soon as possible.

White House officials said the new policy would help illegal immigrants with family members in the United States. The White House is interpreting “family” to include partners of gay and bisexual people.