It's easy to mistake a strong circumstantial case for definite proof - something worth remembering before coming to firm conclusions about whether the Pakistan cricket team are cheats, for example, or whether Andy Coulson definitely knew about phone hacking at the News of the World.
There was a good example of this yesterday - with the decision to suspend snooker player John Higgins for bringing the game into disrepute, but to clear him of allegations he had decided to throw frames for money. The News of the World's original story wasn't couched in any terms other than "He must've done it":
You are, as ever, invited to join the dots - or, more accurately, have the dots joined for you. These kind of entrapment/sting stories do a good job of creating a strong circumstantial case of evidence and then bring about enough noise and shouting and finger-pointing to try and obscure the places where the evidence doesn't quite reach.
You can see this attitude in the News of the World's triumphalism regarding the verdict:
"This result is a victory for News of the World investigative journalism," it read. "John Higgins has been found guilty, suspended and fined. Pat Mooney has been found guilty and banned for life.
"Today's judgement is testament to the extraordinary work of our investigations editor Mazher Mahmood. We hope that the exposure of Higgins and Mooney will act as a deterrent to any other cheats in sport and help restore the integrity of snooker."
Well true, but only partly true. John Higgins has been found guilty of one charge, but not guilty of another. It's misleading to suggest that the News of the World's allegations - that Higgins had agreed to throw frames in return for money - were proven, because that's not the case at all.
Not that it's the case, either, that he's been found to be a completely innocent victim in all this, because he hasn't - but establishing the truth is a complicated thing in these situations. The evidence was deemed by those assessing it to be insufficient to prove all the charges against Higgins - which doesn't necessarily mean that he definitely didn't do it, of course. However, in these kind of disciplinary hearings, as in court cases and other hearings held to determine the facts of a situation, "He must've done it" doesn't count. You can have a lot of circumstantial evidence, but that doesn't prove what you're trying to prove. It can certainly taint someone.
And that's worth bearing in mind with the Andy Coulson side of things. There may be a compelling circumstantial case, to which people might like to add a lot of finger-pointing and noise, but I think it runs the risk of being a bit like the News of the World (ironically enough) if we try and say Coulson must've been involved with the dark arts, without evidence that he must've done it. That may be frustrating and disappointing for those of us who might like to see damage done to the Government, but that's how it is. I've yet to see conclusive evidence nailing him.
It's the same kind of attitude we saw last week with William Hague - you can put down the circumstances and give a wink and a nudge in italics in red crayon, like a big baby - but that doesn't mean that anything's been proved. I know that it's tempting to try and reach the conclusion that you want to reach, in all that excitement, but I don't think it does anyone any good to do so. We might want Andy Coulson to be unmasked as a villain, or the Pakistan cricket team to be exposed as chucking matches, or snooker players to be shown to be chucking games for money, because that's the most exciting outcome and it makes a better story - but if the gloves don't fit, you must acquit. Otherwise you just end up trying to do damage through insinuation and supposition, rather than showing that you've demonstrated your theory properly.
Just saying "They must've done it..." isn't always enough.