Let's try a thread which I don't think has been done to death yet.
Bad things happen, and often we say that people are responsible for those bad things. When do we say that so-and-so was to blame for such-and-such bad thing?
The naïve answer would be that we blame the person whose actions caused the bad thing to happen. For example, if Cronos shoots Scarecrow we blame Cronos for Scarecrow's death because it was Cronos's action (i.e. shooting) that caused the bad thing (Scarecrow's death).
But the naïve answer doesn't work in all scenarios. For example, imagine I'm going on holiday and Jutsu has promised to water my prize orchid while I'm away. If he forgets and my orchid dies we would say that he is to blame for the plant's death. But arguably Jutsu hasn't actually done anything - he didn't water the plant, but I didn't water the plant either, and nor did Exilement. Why do we blame Jutsu but not me or Exilement?
Based on the above example we might want to say that we blame a person for a bad thing if they could reasonably be expected to take one course of action but they took another and that choice led to the bad thing.
Of course, lots of things have more than one cause. Let's continue with the above example, but say I know that Jutsu is forgetful and I ask Camila to remind him to water the orchid. Camila forgets to remind him. Does Camila share a portion of the blame with Jutsu?
Another issue to consider is one of free will. Jutsu obviously didn't choose to forget about the orchid - no one can choose to forget something. And it's not reasonable to expect someone to do something which they never even consider. We might want to blame Jutsu if he was watching my orchid and cackling as it dehydrated, but maybe not so much if the thought of it never occurs to him. And should we bring me back into the blame game for having made the request to someone who I knew was likely to forget?
If we do want to say that I am at least partly to blame for bringing about a situation in which there was a greater than necessary likelihood of the death of my plant, does it logically follow that if Arch-Angel walks home through a dark ally and gets raped he's partly to blame for the rape because he put himself in a situation where rape was more likely than it would have been if he'd gotten a taxi? Since most people presumably don't want to blame a rape victim, that would seem to be a reductio of the idea that I'm partly responsible for the death of my plant.
If more than one person is to blame for something, does the blame get divided between them so that each gets less than if he was solely responsible? During the recent leaks of nude celebrity photos I saw a few people saying that these celebrities were at least partly to blame because in this day and age it's a reasonable course of action not to store nude photos in the cloud. If that's true, does it lessen the immorality of the people who acquired the pictures?
There's a lot to talk about on this issue. If you'd like to boil it down to one specific question it would be "what are the necessary and sufficient conditions under which we say that an individual is morally to blame for something, and how much blame should we assign to them?"
If you'd like to relate this to a specific recent example, I guess you could ask yourself who is to blame for the death of Michael Brown in Ferguson. Is it Brown, who assaulted a police officer, or the police officer who shot him? Who would have been to blame if the circumstances had been slightly different?