When discussing the death penalty, especially for juvenile perpetrators, three concepts are critical: justice, deterrence, and possibility of error. The capital punishment may be seen as just because it causes the same suffering on the criminal as he or she did on his or her victims. However, it also causes undue suffering on the criminal’s friends and family, who are innocent of the crime. This is seen as barbarous and appropriate to a primitive “eye for an eye” notion of justice unfit for a modern society. As a deterrent of future crime, execution is not as effective as a life sentence. Finally, there is always a possibility of error, and if the suspect is already dead, nothing can be done to amend this error.
Specific to juvenile criminals is the fact that their age is a mitigating factor. Before the age of 12, a child must be proven to be capable of formulating criminal intent. As such, one can argue that the suspect’s mental capacity and culpability are diminished, comparable to mentally ill or senile adult suspects. As such, juvenile perpetrators have more arguments against being subject to the death penalty than adults.
In the case of Roper v. Simmons (2005), the Supreme Court argued that juveniles are less responsible for their action than adults. This comes from the argument that juveniles lack the maturity and are more susceptible to negative influences, such as peer pressure, and have less control over their environment. Another major argument was related to consistency, where a strict line between a juvenile and adult was drawn at the age of 18. Additionally, the Court referred to United Nations provisions prohibiting the execution of people under 18, as well as a national sentiment against applying capital punishment to juvenile criminals.