This is clear juror misconduct

I've already made a post about how the guy was clearly guilty. But the main issue isn't what the verdict was, it's how they reached their verdict. The jurors broke pretty much every rule, and in real life it would result in a mistrial. I'm not a very good writer, so I'll copy and paste from a Cracked article:

"The guy should have been kicked off the jury the moment he went out and bought the knife. By law, juries are not allowed to conduct their own investigations, and if the other jurors had just reported Juror No. 8 for that, he'd have been replaced by an alternate. Yes, it's cool for characters in a movie to take the law into their own hands. In real life, you like to leave tasks like that to the people who have years of training and law enforcement experience.

But that aside, Juror No. 8's whole line of reasoning is wrong at almost every step. According to the law, it's the jury's job to determine the veracity of the evidence presented, as is -- not to question and interpret the evidence any way they choose and make wild assumptions about witnesses. For instance, you don't just dismiss blood evidence as "probably planted or some shit" unless you are presented with evidence that it has been planted. Likewise, you can't just hand-wave away jury testimony based on, "Her eyes are probably bad."

It's kind of important that people stick to their roles in the criminal justice system. It's the lawyers' job to pick apart witness testimony and find any inconsistencies, just as it's the cops' job to hunt down evidence, and it's the prosecutor's job to present it. Once a juror decides to start doing all of that stuff himself, it's probably time to find a new juror."

http://www.cracked.com/article_18815_the-5-most-wildly-illegal-court-rulings-in-movie-history.html

If you don't think it's a big deal, just imagine if it was reversed. Just imagine if Henry Fonda convinced the jury to send a possibly innocent man to death row like that.