What's accountability?

Henry Farrell at Crooked Timber makes some points that should be obvious, but strangely aren't:

...In many countries (including my home country, Ireland), police have a reputation for stitching people up; they seem prepared in some instances to commit perjury in order to get people convicted for crimes. Now in some cases, this is a completely cynical exercise – the police have no idea of whether the accused is guilty or not, but need to get a conviction for political or other reasons. But in others, it’s because the police think that they know who committed a crime, but don’t have the necessary evidence to get the person convicted in court. Therefore, they perjure themselves and lie about the evidence in order to get the conviction.

This, it seems to me, is what happened in the lead-up to Iraq. The Bush administration, like others, probably did genuinely believe that Iraq had an active nuclear program. But it didn’t have the necessary evidence to prove this, either to its allies or to its own people. It therefore cooked the evidence that it did have in order to make its claims more convincing. It didn’t deceive the public about its basic belief that there were WMDs in Iraq. But it did deceive the public about the evidence that was there to support this belief, in order to convince them that there was a real problem. In other words, it did “consciously mislead” the American people (and its allies). When the police are caught perjuring themselves to get convictions, they should (and frequently do) suffer serious consequences, even if they believe that they’re perjuring themselves in order to get the guilty convicted. That’s not what the police should be doing; they haven’t been appointed as judges, and for good reason. If the police persistently lie in order to get convictions, the system of criminal law is liable to break down. Similarly, when the administration lies about a major matter in order to get public support, it shouldn’t be excused on the basis that it thought that it was lying in a good cause. It’s still betraying its basic democratic responsibilities.

That's nice and all, but the media's opinion seems to be that if there's no blowjob, it's not worth impeaching over. Again, I've never taken a moral philosophy course, but it seems like misleading people about WMDs in order to go to war is definitely worse than misleading people about blowjobs. (Maybe "James Hunter" can tell me why I'm wrong.)