In its coverage of the rape trial in Ohio, CNN contributors decided that they felt oh, so very sad for the poor little rapists because the crime would be on their permanent record, even though they were tried as juveniles. "Think of the promising things these little rapists could have accomplished!" they lament. "They are only little kids," they cry. As far as I can tell, there is no magical flash of self-awareness and ethical judgment that comes when an individual goes from 17 years and 364 days to 18 years; 16- and 17-year olds know what they are doing (even though separate juvenile detention has value for their safety).
Even though I don't believe that minors should be excused for their errors in judgment or in action, I do agree that there are some crimes that should not stay on their record permanently: crimes in which either (a) there is no victim other than the person him/herself (drug possession, underage drinking) or (b) that which is taken can be given back (petty theft, shoplifting). There is no reason to inflict permanent punishment for a victimless crime, and in the latter case, stolen objects can be returned (with interest, if needed)---a settling of debts, if you will. However, rape and murder are both perfect examples of crimes that meet neither specification; there is a victim, and that which was taken can never be given back. (Torture would also fall into that category).
I would also argue that permanent records for rape and murder are also important for the safety of future significant others of the perpetrators. Every future girlfriend or potential girlfriend of the convicted rapists in Steubenville have the right to know that these guys are rapists.
I think it's important to address another problematic argument that always comes up when people express their sympathy for the minors who committed such crimes. The actions committed are called "mistakes." A "mistake" is an accident, a failure of interpretation. It differs from an error, which is a sign of misguidance, of a failure of judgment or of knowledge. If I see 2+2 and answer 5, that is an error. If I see 2+2, but in my hastiness or weak vision, I see 2-2, and say zero, that is a mistake. Clearly, these kids did not commit a simple "mistake."