President Bush was like Tom Sawyer. He got his staff to whitewash investigations for friends. Even though the Bush administration is out of power, ex-members lobby the Obama Justice Department. They seek to soften conclusions from a five year Bush internal investigation into torture.
Maybe George W. should have released the report before he left office. But that would've require a surge of pardons. It's hard to have one's cake and eat it too, at least while being waterboarded!