WASHINGTON — Four of the nation's most highly valued terrorist prisoners were secretly moved to Guantanamo Bay, Cuba, in 2003, years earlier than has been disclosed, then whisked back into overseas prisons before the Supreme Court could give them access to lawyers, The Associated Press has learned.

The transfer allowed the U.S. to interrogate the detainees in CIA "black sites" for two more years without allowing them to speak with attorneys or human rights observers or challenge their detention in U.S. courts. Had they remained at the Guantanamo Bay prison for just three more months, they would have been afforded those rights.

"This was all just a shell game to hide detainees from the courts," said Jonathan Hafetz, a Seton Hall University law professor who has represented several detainees.

Removing them from Guantanamo Bay underscores how worried President George W. Bush's administration was that the Supreme Court might lift the veil of secrecy on the detention program. It also shows how insistent the Bush administration was that terrorists must be held outside the U.S. court system.

Years later, the program's legacy continues to complicate President Barack Obama's efforts to prosecute the terrorists behind the Sept. 11, 2001, attacks.

The arrival and speedy departure from Guantanamo were pieced together by the AP using flight records and interviews with current and former U.S. officials and others familiar with the CIA's detention program. All spoke on condition of anonymity to discuss the program.

Top officials at the White House, Justice Department, Pentagon and CIA consulted on the prisoner transfer, which was so secretive that even many people close to the CIA detention program were kept in the dark.

CIA spokesman George Little said: "The so-called black sites and enhanced interrogation methods, which were administered on the basis of guidance from the Department of Justice, are a thing of the past."

Before dawn on Sept. 24, 2003, a white, unmarked Boeing 737 landed at Guantanamo Bay. At least four al-Qaida operatives, some of the CIA's biggest captures to date, were aboard: Abu Zubaydah, Abd al-Nashiri, Ramzi Binalshibh and Mustafa al-Hawsawi.