In Snape’s defence ...

If there was any cause for doubt during those years or any lack of sincerity on Snape’s part, Dumbledore, “blessed as I am with extraordinary brainpower” had plenty of opportunity to find him out.

In addition, Ladies and Gentleman, I put it to you that the impact of a Death Eaters’ spree at Hogwarts was nowhere near as extensive as it might have been. And who was it who took charge, limited the damage and who got the Death Eaters out of Hogwarts as quickly as possible? It was Severus Snape, “It’s over. Time to go.” Snape parried curses in his flight but did not retaliate. In addition, he actually forced a Death Eater to lift the Cruciatus Curse from Harry, “Have you forgotten our orders? Potter belongs to the Dark Lord - we are to leave him! Go, Go!”

Clearly Dumbledore knew this would be Severus Snape’s last year at Hogwarts. Otherwise he would not have given him the Defence Against the Dark Arts job that Snape had reputedly wanted for years, “we have never been able to keep a Defence Against the Dark Arts teacher for longer than a year since I refused the post to Lord Voldemort”.

Dumbledore and Harry had just returned from the mission for the Horcrux in the cave and Dumbledore was desperately weakened by the potion he drank in order to secure the locket. Before the Dark Mark was sighted above the castle, his one thought was to get back, his one plea, “I need Severus ...” It was to Severus that he returned injured after retrieving Marvolo’s ring and it was Severus that he insisted on seeing after the misadventure in the cave.

Naturally we all assumed that was to secure an antidote to the deadly potion and quite possibly that was the initial reason, but what if the reason changed once Dumbledore saw the Dark Mark above the castle and knew what that must mean? The antidote theory does not explain why Dumbledore immobilised Harry on the battlements. But if, once Dumbledore saw that Dark Mark above the castle, he expected Draco to make an attempt on his life and suspected how that situation must play out, that would explain his immobilisation of Harry - to keep him safely out of the action when Snape came to finish him off. He then begged Snape to go through with it, “Severus ... please ...”

I submit that the hatred and revulsion on Snape’s face that night was self-hatred and revulsion for the task he had to perform.

Ladies and Gentleman of the Wizengamot, the use of the Unforgivable Curses must not be authorised in this case! I put it to you that Severus Snape may indeed be the Dark Lord’s right hand man but that there is enough evidence to stay your decision until further evidence comes to hand which may show him in a more complimentary light.