By Jessica Dye

NEW YORK, Feb 14 (Reuters) - Sex offenders involuntarily committed to psychiatric institutions following their criminal sentences can move forward with a 2008 civil rights lawsuit against New York officials, the 2nd U.S. Circuit Court of Appeals ruled Thursday.

It held that former New York governor George Pataki and state mental health officials and corrections officers were not entitled to qualified immunity from the lawsuit.

A reasonable official "would have known that the process by which the plaintiffs were being committed did not satisfy basic constitutional requirements," U.S. Circuit Judge Robert Sack wrote.

The decision affirmed a 2010 ruling from U.S. District Judge Jed Rakoff in Manhattan.

A spokeswoman for the New York attorney general's office declined to comment.

The lawsuit was filed in 2008 by a group of sex offenders who claimed they had been committed to psychiatric institutions without notice or a hearing after they had served their criminal sentences.

In addition to Pataki, the defendants were officials from the state Office of Mental Health and the Department of Correctional Services.

The commitments stemmed from the Sexually Violent Predator Initiative launched by Pataki in 2005. It called for sexually violent predators to be evaluated for involuntary civil commitment before being released from prison, the ruling said.

The lawsuit alleged that confinement without a hearing or notice violated plaintiffs' rights to procedural due process.

The defendants moved for summary judgment, arguing there was no legal prohibition against brief periods of prehearing confinement, provided that an opportunity for a hearing was offered in a timely manner. According to the ruling, they also claimed qualified immunity.

On that basis, in 2010, Rakoff denied the motion on the procedural due-process claim. He also concluded that the plaintiffs' civil confinement "did not remotely comport with constitutional requirements."

The defendants appealed, and the 2nd Circuit on Thursday affirmed the district court.

"(A) prisoner - even one convicted of an atrocious crime - maintains a liberty interest in the conditions relating to the essential nature of his confinement," Sack wrote.

Sack was joined by Judges Joseph McLaughlin and Peter Hall.

A lawyer for the plaintiffs, Ameer Benno, said he was gratified by the 2nd Circuit's ruling on qualified immunity.

The case is Bailey v. Pataki, 2nd U.S. Circuit Court of Appeals, No. 10-2563.

For the plaintiffs: Ameer Benno, Richard Sullivan and Jeffrey Rothman of Benno & Associates.

For the defendants: Cecilia Chang, Barbara Underwood and Benjamin Gutman of the New York attorney general's office.

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