yup. if he'd done whilst the guy was threatening then fine but if it was when the guy was leaving then he was not endangering his life therefor not self defence/reasonable force. go not pass go. do not collect £200.
There is always a discretion in certain circumstances whether to prosecute or not. Jip, I wonder if your schoolmate went down for murder if he too left him to die. I think that was the issue in the Tony Martin case where he shot the burglar and left him to bleed to death.
From what I can remember, the dying bloke managed to drag himself out of this lad's flat, and somehow make it down the stairs before kicking the bucket. The lad just locked his door, worried about more of them coming back.
The fact he was in possession of Drugs and a feckin Samauri sword probably didn't really work in his favour
It was just a bit of weed, but yeah, the 3 foot of razor sharp steel probably didn't do him any favours