But does anyone believe it now? From the WH statement:

I understand and share her concern, however, about the current state of the Supreme Court confirmation process. It is clear that Senators would not be satisfied until they gained access to internal documents concerning advice provided during her tenure at the White House — disclosures that would undermine a President’s ability to receive candid counsel. Harriet Miers’ decision demonstrates her deep respect for this essential aspect of the Constitutional separation of powers — and confirms my deep respect and admiration for her.