(The following comments are based on the question about the justice system, and not this girl's case in particular)
I agree that the justice system has some major issues. The basic idea is good, except I personally would overhaul a number of sentences for particular crimes, and forget about parole. Unfortunately, it doesn't work the way it's intended, and whether we like it or not, the justice people get is that which they can afford.
I wouldn't say that none of us believes in murder...in fact, my husband and I were just discussing this the other day. It all really comes down to your opinion on morality -- does the end justify the means, or is each action inherently good or evil in and of itself? I like to look at it as yes, it is bad to steal, but isn't it worse to let your family starve because you didn't? I personally believe that in many cases, the ends justify the means, and as such there are times when murder is not wrong (i.e. killing someone in order to protect yourself or your family). Taking the question another way...obviously, I believe that murder exists, it happens all the time. That said, I don't believe that the government should have the power over life and death, but that what are now death sentences should be life sentences at hard labor with no possibility of parole.
The jury system is as polluted by emotional idiots as the general population, in my opinion. In other words, every single trial has just as much chance of getting a jury that is ruled by emotion as one that is ruled by logic, it all depends on who happens to get called in and make it through jury selection. For big trials, a lot is decided by which lawyer happens to be a better character judge and selects the best jury for their own means.