This is a judicial review to show that the government acted unlawfully in blocking an independent enquiry into the legality of the war under international law, even if the courts agree that the government acted illegally in blocking the independant enquiry all that will mean is that an independent enquiry will take place. Blair won't stand trial. I agree that he should stand trial, but it's not clear that it's illegal - as opposed to grotesquely immoral - for the primeminister to take the country to war on any basis. If they can show that he lied to parliament then they've got him for lieing to parliament; but the use of the armed forces comes under Royal Perogative which basically means he can do what he wants with them.