In finding John Yoo has immunity, the Court wrote:
“There was at that time considerable debate, both in and out of government, over the definition of torture as applied to specific interrogation techniques...“In light of that debate...we cannot say that any reasonable official in 2001-03 would have known that the specific interrogation techniques allegedly employed against Padilla, however appalling, necessarily amounted to torture.”
The opinion is here.
The Court also ruled that detainees held in military custody don't have the same rights as prison inmates.
As to torture, the Court says:
although it has been clearly established for decades that torture of an American citizen violates the Constitution, and we assume without deciding that Padilla’s alleged treatment rose to the level of torture, that such treatment was torture was not clearly established in 2001-03.
As Marcy at Empty Wheel points out, Jay Bybee, co-author of some torture memos, is now a 9th Circuit Judge.
It's also interesting to me that Yoo's attorney in the case is Miguel Estrada, who Bush nominated for the D.C. Circuit Court of Appeals in 2003, and whose nomination caused a firestorm and filibuster based on his ideology. Normally I caution against inferring a lawyer shares a client's ideology based only on his or her agreeing to take the case, but with Estrada, it's pretty unmistakable he and Yoo have a lot in common. Estrada finally withdrew his name from consideration.
Estrada is a partner in firm that represented George W. Bush in the Supreme Court during his 2000 post-election battle with George Bush. He was on Rudy Giuliani's judicial advisory committee when Rudy contemplated running for President and promised conservative judges.
For anyone who has forgotten what was encompassed in the torture memos, see here. Here's Time Magazine: Jay Bybee, the Man Behind Waterboarding.
The ACLU has some of the torture memos authored by John Yoo here.
Here are the Judiciary Committee's documents including the Office of Professional Responsibility Reports. OPR initially found Yoo and Bybee committed professional misconduct. Its final report found the same. But here's the Memo from the Associate Deputy Attorney General, David Margulis refusing to adopt the OPR's findings.