Guys, I came across this about a year ago. There is a lot of science involved (highlight added).
"Meanwhile, legislatures and courts are hearing a very different argument from a group of people that haven't traditionally testified before them: neuroscientists. Using advanced brain-scanning technology, scientists are getting a better view of how the human brain develops than ever before. And what they've found is that in most people, the prefrontal cortex and its links to other regions of the brain are not fully formed until age 25--much later than anyone had realized. These areas are the seat of "executive decision making"--the parts of the brain that allow people to think through the likely consequences of an action, weigh the risks and benefits and stop themselves from acting on impulse. In other words, the stuff that makes you a mature person."
