Regarding your first paragraph, I will certainly agree that the stipend for jurors is far too low. It hasn't moved in I don't know how long. It definitely plays into it. I don't necessarily agree with your sentiment about "why should I have to" since unless anyone does, then no one does and injustice continues. I say this knowing full-well my situation is very different than so many others and in many ways, I have the luxury of thinking this way. I am very cognizant that most aren't. And trust me, as an aside, lawyers are excluded from being jurors, but I sure as hell would want to be one.
I think your second paragraph is exactly the sentiment I wanted to speak to. If one gets to the point of feeling like no matter what, they can't make a difference, because of years of things going the other way, that to me is apathy. The reasons for the apathy are very, very understandable, but it is the sentiment. Despair can be another. Regarding bail, that is determined as to whether the individual is a risk to public safety. He was deemed not to be. You can say, and I will support the argument, that racism plays into that determination, but that is the reason.
As for your question: the witness' intoxication levels has nothing to do with the admissibility of their evidence. It can play into the credibility, and probably did (and should) but the evidence was admissible. As a prosecutor, I would have argued manslaughter more fervently, with a different angle.. i.e. that Stanley didn't mean to pull the trigger, doesn't remember, but most likely did and that there is no reasonable doubt to believe that he didn't. It's also very easy for me to say behind this keyboard and not handling the case. That said, manslaughter was an option to the jury and they declined it, so it was before them to decide it was manslaughter if they wanted to.