Although I have no interest in "Gamergate", I found this essay by Ezra Klein on increasing political polarization interesting. One point that struck me was Klein claims that while polls showed no difference between Republicans and Democrats in their opinions about the 1984 case in which Bernard Goetz shot 4 young black men on a New York City subway (only 15% disapproved) there was substantial disagreement about the recent (2012) incident in which George Zimmerman shot Trayvon Martin with 20% of Republicans (vs. 68% of Democrats) dissatisfied with the verdict (Zimmerman was acquitted). I haven't tried to verify Klein's claim but if the quoted polling data is even close to accurate this is pretty striking as by any objective standard Zimmerman was far more justified in shooting than Goetz was.
If you don't remember the case, Goetz shot a group of 4 young black men on a New York City subway after one of them approached him and aggressively asked for $5. While no doubt annoying and possibly intimidating it is really doubtful that this was sufficient legal justification for pulling a gun and shooting all 4 of them. Goetz apparently realized this as he fled the scene. But the jury saw it differently convicting Goetz only of a weapons charge (he was carrying illegally) a verdict that is difficult to defend in strictly legal terms.
Zimmerman on the other hand shot Martin (with a gun he was carrying legally) because Martin was sitting on his chest and punching him in the face. Zimmerman didn't flee the scene and the jury properly found him not guilty.
One can speculate about the reasons for the difference in public opinion about the cases but one factor seems clear. The initial press coverage was sympathetic to Goetz but hostile to Zimmerman and to quote Mark Twain "A lie can travel half way around the world while the truth is putting on its shoes.”