I agree with you Gareth, but only up to a point.  I believe personally that the motive behind why a person breaks the law should have some bearing on the case.  It seems to me that the man is being tried on terrorism charges, stealing information etc.  Yet he was looking for secret files on UFOs, which can hardly be said to be a terrorist concern, or a threat to Western security.

One article I read this weekend on the case said this: "These (secret UFO files) aren't the secrets the US establishment fears being revealed; it's the notion that a self-taught hacker ... could wander at will through the firewalls of the world's largest military industrial complex that has really irked the forces of law and order ... McKinnon is being punished for their embarrassment at the revelation that their security isn't very secure at all.  So now, instead of receiving a slap on the wrist, McKinnon could be imprisoned for up to 70 years ... For now he's going to have to pay the price for Uncle Sam's discomfiture at being caught with his trousers down."  Scotsman, 21 Sept 2009, http://tinyurl.com/6bqz98

I'd agree that he should be imprisoned if he'd been stealing information to sell to terrorists.  But he was trying to find info on UFOs.  The punishment should fit the crime, he shouldn't be punished for the paranoia of the US government.
Alison