The prosecutors killed Swartz.
That is utterly moronic. The prosecutors just did their job. It is not their job to decide if the law is just, or decide if people the police (or anyone else who has gathered enough evidence) accuse of a crime is innocent. It is their job to go do their very best to get people the police accuse of a crime found guilty at any cost (even if their personal opinion is that they are innocent). It is the defence teams job to get their client off at any cost (even if he is guilty as hell).
The only people who get to decide guilt or whether a law is just (ie - fair) are the jury. http://en.wikipedia.org/wiki/Jury
The only thing the prosecutor can say to drop a case is that there is insufficient evidence to support a prosecution (they of course may try to get you to plead guilty first to save face but that is fair game).
None of this is to say I think what happened to Aaron Swartz is fair. But the points above are the principles under which a adversarial legal system operates: http://en.wikipedia.org/wiki/Adversarial_system
In this case someone wanted to prosecute Aaron Swartz. The prosecutor looked at this and decided their was a realistic chance of a successful prosecution. Aaron chose not to wait for a jury to decide his guilt and killed himself. If he was innocent of any crime a jury would hopefully have found him so, but he lacked enough faith in the system I guess but I nor anybody else can be 100% about his reasons, especially since he left no explanation. We can make an educated guess, but that is very different from certainty.
I find the idea of blaming any one part of the system in this case to be wrong, especially as the part everyone blames was only doing what they were supposed to. When a guilty person gets off it is not the fault of their defence lawyer for doing their job too well, it is a breakdown of the system as a whole. I think the same applies in this case, blame the entire system not a single cog within it.
This is just one further example of a shortcoming within the US legal system but every legal system has short comings, inquisitorial legal systems have their downfalls too.
The big issue here though is actually particular to the US system in that in order to drive down costs, more and more cases are now settled without a jury being involved by the prosecution doing its damnedest to scare the defendant into a pragmatic guilty plea to save the cost of a trial. This happens in millions of cases and probably does save lots of money and most of time gets the right outcome, in this case some poor guy who was out of his depth was literally scared to death by it.
Maybe the solution here is to make jury trials the norm instead of the exception whatever the cost. Since juries were designed to prevent shit like this they have to be available to all, not just the few who can afford them.