This is Whataboutism 101 though. Other things that happen in society are irrelevant to this case. The only issue pertenant are that a man shot a 16 year old boy because the 16 year old knocked on his door. There was no other interraction between the 2. The old man's defense is 'he was big and tall' and he claims he tried to enter the house. The boy's testimony states that he removed the door cover to knock on the door. You can not knock on the door without removing this cover, otherwise it would damage the cover. If this is true the boy did not attempt to enter the man's home. So we then have to ask if this is fair and reasonable force for the threat. If there is no justification it becomes attempted murder. The motivation of the crime isn't that relevant but frankly it just so happens he hasn't shot anyone else knocking on his door but he has shot a black boy and that would indicate he is either more scared or prejudiced against young black males. If I was his lawyer I'd try to have the old man declared to be suffering from senility and not in a fit state of mind as a line of defence.
I also think most reasonable people would be less concerned about whether this man is branded a racist, which in itself maybe simplistic, and more concerned he's commited a heinous crime and is a threat to society. His ex-wife also said she believed him to be a violent man, which is in itself more concerning the simply being prejudiced:
She said his alleged crime did not shock her. 'I was always scared of him,' she told the newspaper. 'It doesn't surprise me, what happened.'
Clayton said that during their marriage he would frequently become violently angry and smash objects in their house.
When she reported him to the police, she said, the officers told her that it was his house and he could do as he pleased. She said she did not know about his alleged crime until her daughter rang her and told her.