One thing the Clinton and Bush Administrations have in common is the excessive (and improper) assertion of executive privilege. In Clinton's case, some of the erroneous privilege claims concerned the health care task force and the Monica Lewinsky scandal (see, e.g., here). Remember the effort to claim a Secret Service "protective privilege"?
The Bush Administration is stretching executive privilege as well. As Douglas Kmiec discusses here and here, the Bush Administration is stretching the legitimate use of the privilege in refusing to allow testimony related to the U.S. attorney firings and detention policy. According to Kmiec, the excessive assertion of executive privilege has consequences beyond the immediate controversies. Among other things, it makes interbranch relations unnecessarily adversarial, facilitates bad advice, and may cover special interest manipulation of executive policy-making. Executive Privilege has a valid purpose, but that purpose is undermined when the privilege is invoked unnecessarily.