Jack Straw manages to avoid investigation into rendition flights by shifting the burden of proof, claiming that if it had been going on, "it is a fair bet that somebody would have spotted this". In other words, if you can hide something well enough (reading "hide" equally as "repress", "obscure", "mock" or "plain ignore") then it might as well not be happening, and in that case there's no need to check it out.
Precaution is a funny word. In a time when more and more people are being tagged as suspicious until proven innocent, precaution is becoming a way of life. (Precaution and paranoia often start to get blurred too, but that's for another post.) Yet here, once again, we can see it's one rule for the masses, and another for the boys in charge.
Suspicion and evidence are 2 very different things, but the way things are going, the latter will soon be the de jure of the people in charge of the investigations, while the rest of us, whose "power" extends to an exercise in formality once every 4 years, gets left with the fear.