以下感謝 oompa 提供的資料

在台灣未成年人除非是惡性重大如殺害直系血親才有可能被判死刑或無期徒刑
http://www.deathpenaltyinfo.org/art...scid=38&did=885
但可以看看上面網頁
美國該判死刑就判死刑不給機會的
美國直至去年，才有未成年犯最重無期徒刑

New York Times Article on the Science of Adolescent Brain Development
As the U.S. Supreme Court considers Roper v. Simmons, a case that will determine the constitutionality of executing juvenile offenders, new scientific research continues to emerge regarding the brain development of those under 18 years of age. New MRI-based research has shown that the brain continues to develop and mature into the mid-20's, and that prior to the completion of this process, adolescents use their brains in different ways than adults. For example, teens often operate from a more instinctual and reflexive part of the brain, and researchers have found that adolescents in stressful situations lack the ability draw on certain parts of the brain that are fully developed in adults to control their behavior. "This is why kids who are good kids, who know right from wrong, sometimes do stupid things. They act on impulse," said Dr. David Fassler, a psychiatrist in Burlington, Vermont, and a spokesman for the American Psychiatric Association. The article in the New York Times Magazine quoted the brief of the American Medical Association: "Scientists can now demonstrate that adolescents are immature not only to the observer's naked eye but in the very fibers of their brain. Normal adolescents cannot be expected to operate with the level of maturity, judgment, risk aversion or impulse control of an adult." While the medical community is quick to point out that these scientific developments do not excuse the actions of teen offenders, they do believe that these developments prove that juvenile offenders are less culpable than adults and should not be held to the same standard as those whose brains are fully developed. (The New York Times Magazine, October 17, 2004).