Approval for warrantless surveillance is given on a case by case basis, as are warrants, hence the ongoing nature of the approval process.
The evidence is equivocal, but appears to point to a different reason for the balk by Comey.
SUNDAY, MARCH 14, 2004
WWW.USDOJ.GOVWASHINGTON, D.C.-- Attorney General John Ashcroft was discharged from the George Washington University Hospital shortly after noon today, March 14, 2004.
Attorney General Ashcroft entered G.W. Hospital on March 4, 2004 with a severe case of Gallstone Pancreatitis. On March 9, 2004, Attorney General Ashcroft underwent surgery to remove his gallbladder which contained several gallstones that were of concern to the doctors.
http://www.gwhospital.com/p13762.html
In mid-2004, concerns about the program expressed by national security officials, government lawyers and a judge prompted the Bush administration to suspend elements of the program and revamp it.For the first time, the Justice Department audited the N.S.A. program, several officials said. And to provide more guidance, the Justice Department and the agency expanded and refined a checklist to follow in deciding whether probable cause existed to start monitoring someone's communications, several officials said.
A complaint from Judge Colleen Kollar-Kotelly, the federal judge who oversees the Federal Intelligence Surveillance Court, helped spur the suspension, officials said. The judge questioned whether information obtained under the N.S.A. program was being improperly used as the basis for F.I.S.A. wiretap warrant requests from the Justice Department, according to senior government officials. While not knowing all the details of the exchange, several government lawyers said there appeared to be concerns that the Justice Department, by trying to shield the existence of the N.S.A. program, was in danger of misleading the court about the origins of the information cited to justify the warrants.
Bush Lets US Spy on Callers Without Courts
By JAMES RISEN and ERIC LICHTBLAU | New York Times | December 16, 2005