I saw Barry Scheck of the Innocence Project speak today along with Alan Newton, who spent 22 years in prison before DNA evidence proved he was innocent. It is pretty riveting stuff. They have freed hundreds of innocent convicts.
Newton has a mesmerizing demeanor. I'm not sure how old he is--presumably in his forties, if not early fifties--but he looks much younger, and has a certain scary concentration in his demeanor that you sense is at least partly the result of the mental effort of staying sane and fighting for his life while locked up in jail for two decades. (Scheck alluded to many innocent prisoners who "implode," "go crazy," "give up," or "lose the will to fight.")
Both men discussed two kinds of evidence that seem solid but are unreliable: eyewitness testimony and confessions. Eyewitness testimony is just notoriously shaky. When presented with a lineup, witnesses will often pick the person who looks most like the person they saw... even if it's not identical to the person they saw.
And DNA evidence has proven that numerous defendants who confessed were actually innocent--they confessed because they were threatened, lied to, or worn down by long interrogations. One 16 year old (Tankleff... if you live near NY or NJ you may know this one) confessed to his father's murder after being told his father had woken up, been shot up with adrenaline, and identified his son as the killer. Another man confessed to five rapes after hearing about the sentence he was likely to receive if he didn't take a deal... the actual rapist then traveled around the country for years, raping hundreds of women.
Oh yeah, one another thing: the Innocence Project is one of the many social justice programs and charities badly burned by the evil sociopath Bernie Madoff (how has this man not committed suicide yet? come on, Bernie... YOU CAN DO IT).
I just donated some money to them. Consider doing so, it's a good investment in your mood in addition to being a good thing to do.