I think the discussion is a little bit misguided. I would go as far as saying a lot more than a little bit and completely misguided. I think it's focusing a bit much on refuting that GT's 'life wasn't threatened' by Ms Wright. It probably wasn't.. he was a big man and she was tiny. The evidence led so far suggests he wasn't really injured that much. Zero relevance.
The recording does suggest she was doing something, at least, to him, which might have caused him minor injury. This is all that is relevant. If she was using only the smallest smidgeon of force against him, this is an assault and what is relevant.
I think the overwhelming opinion here is that that yes, a smidgeon of force was being used against him by Ms Wright.
It does not matter that Ms Wright died in a very sad and horrible way. What matters is Tostee did not actually apply to her the force that killed her. The force he used was just enough to flick the latch on a door.
The reason this is so important is because GT is relying on s 271 of the Queensland Criminal Code, which reads as follows:
271 Self-defence against unprovoked assault 271 Self-defence against unprovoked assault
(1) When a person is unlawfully assaulted, and has not provoked the assault, it is lawful for the person to use such force to the assailant as is reasonably necessary to make effectual defence against the assault, if the force used is not intended, and is not such as is likely, to cause death or grievous bodily harm.
http://www.austlii.edu.au/au/legis/qld/consol_act/cc189994/s271.html
Lets break it down into the elements:
1. When a person is unlawfully assualted?
I think the evidence can be viewed in such a way to suggest that force was used against GT without his consent. We'll tick a yes on this one.
2. Has not provoked? The jury could be out on this one. (See s 272) -
I think the evidence and audio so far suggests she just got a bit drunk and started being a bit physical with him without him really doing much to provoke her.
3. it is lawful for the person to use such force. -
This makes the force used a legal act.
4. Was the force used reasonably necessary to make an effectual defense against the assault?
This is the kicker. This is why he walks free. All GT did was push her out onto the balcony and lock the door. He didn't really feel overtly threatened, evidence by his 'bad girl remark' but she was going at him enough for him to warrant doing something to prevent the stone throwing or whatever was occurring. And the extremely relevant fact is that
all he did was push her out onto the balcony. The force used could have been much worse - he could have brought the full front of his size advantage and hurt her badly. He reacted in a minor way to a minor attack by merely pushing a door closed and locking it. This is why the defence is not really pushing to prove he was mortally injured. It's not a flaw in his case it's not relevant.
5. Was the force used intended to cause death or GBH?
Interested... this comes down to foreseeability and causation and also, importantly, Ms Wrights free will. The audio recording suggests she was locked out and climbed over in a very short period of time. Between the door slamming and the scream is very brief. The short period of time elapsing erodes away the argument any reasonable person could have seen it coming. The evidence could support the theory GT was even turned around and not looking, given he appears he didn't know if she was dead or not (but strongly suspected it) later on.
His strongest argument is that the force used was only intended to close and lock a door.
The second argument here is her free will. Assuming she just chose to do it so suddenly out of drunken bravado, a person exercising an independent act will always interrupt the chain of causation unless it's a given they'll react that way. This is why it's not manslaughter either.
Standard of Proof
The thing about raising a defence is, you don't need to prove it on the same standard of proof as the crown.
They're on beyond reasonable doubt. If you can raise a defence on the balance of probabilities (50/50) (which I suggest I have given my points on the evidence above) - the prosecution job is to then negative that defence beyond a reasonable doubt.
Not only do they have to prove the elements of murder, beyond any reasonable doubt, they have to prove that self defence doesn't apply
beyond a reasonable doubt also.
This is where the crown case fails. The best case has been put forward by the crown already - now it's just flavour text. Not one piece of evidence yet has really buried the possibility of self-defence. And that's what the crown can't do.
Conclusion
Absolute tragedy though. Absolutely terrible accident to happen.
**edited so as not to detract from being right**
*opinion only