The Department provides an army of analysts and bureaucrats to support the Secretary, and its their responsibility that he doesn't make a fool of himself on the public stage by using incorrect or false data. It's well known that a lot of them did, in fact, push back on some of the absurdities contained in the initial documents provided by intelligence agencies [1], but when it became clear that most of the material was of that sort, they should have smelled a rat and should have told Powell the risk was too high. Your boss losing any credibility on the political and international stage is the worst possible scenario for any SD official.

[1] http://articles.latimes.com/2004/jul/15/nation/na-powell15