Emptywheel (Marcy Wheeler) has done a fabulous bit of sleuthing, and posts the results at The Next Hurrah: The Briefing Dates.
The key point is that Congressional leaders were briefed about secret (and IMHO illegal) wiretap programs so long as the administration thought they were legal — but the briefings stopped when they started to have doubts:
For the first two years of the program, the Intelligence Committee leaders were briefed fairly regularly, at least every 6 months. (It was just the Intell leaders at that point, and not the party leaders, because BushCo went on a snit after Richard Shelby leaked the news that the NSA had had an intercept from Al Qaeda before 9/11, and cut back who it briefed even more than normal; finally, though, the leaders rebelled and they began to get briefed on the big secrets too.) And they seemed to be very diligent to make sure that everyone got equal briefing. For example, when Bob Graham missed the March 5, 2002 briefing, he got his own briefing not long thereafter.
The March 10 Meeting
But then, there was an unusually long gap between briefings, from July 17, 2003 to March 10, 2004, a gap of eight months rather than six. If they had followed the previous pattern, they would have done a briefing in January, 2004.
Note, this was right during the period when Jim Comey, Jack Goldsmith, and others, were recognizing that the program was illegal. So they didn't brief Congress on the program when they discovered it was illegal, but rather let it go for two more months, until the day Comey refused to certify its legality, before they bothered to convene. Effectively, rather than warning Congress, they created a crisis, presumably creating more pressure on Congress to approve it.
Effectively, the March 10 meeting was Tom Dashcle's only briefing on the program. Perhaps that's why he forgets the meeting? Wouldn't you think he'd remember it all the more?
Also note, Tom DeLay got his very own personal briefing on March 11, the day the program operated with no legal sanction. Oh to be a fly on the wall at that meeting…
Things get a little sketchy after that. Congress did not receive a briefing after the crisis, so they presumably didn't learn that the program operated illegally (well, maybe DeLay did, but he's kind of fond of illegal activities). Just Pete Hoekstra got a briefing on September 24, 2004, and he presumably got that solely because he had just taken over as Chair of HPSCI after Porter Goss became DCI the day before. Harry Reid had to wait much longer—two months—before he was briefed on the program after becoming Minority Leader in the Senate in 2006. Effectively, though, the program went almost a full year (March 10, 2004 until February 3, 2005) before Congress was briefed on the program that had been found to be operating illegally.
All this has increased salience this week, because basket case Attorney General Gonzales testified that back when he was White House Counsel, he got an OK to proceed with a/the program from the Congressional leaders which led Gonzales and Card to ambush Ashcroft in intensive care.
There's lots more in the original post. Sen. Rockefeller again emerges looking spineless on an intelligence issue. There is evidence for the proposition that Speaker Pelosi is smart as hell.