Juveniles lack the neurobiology to know better
Once legal prosecutors understand the development of the human brain, it is clear to see that juveniles should not be tried as adults. The brain finishes maturing in the mid-twenties, and it forms back to front. However, until the front of the brain finishes growing, it is possible to see narcissistic, psychopathic, and callous traits. The last aspect to develop is also the part of the brain that deals with the consequences of actions. Without this in place, people can behave in very impulsive ways. These traits can easily be mistaken for ASPD or psychopathic traits. Therefore, in a juvenile's brain, the connections between the emotional part of the brain and the decision-making center are still developing - and not always at the same rate. This is why teenagers specifically have such overwhelmingly emotional input and can’t explain later what they were thinking. Therefore, prior to the maturation of the brain, there is no way of knowing if the juvenile’s emotional reasoning has been fully developed and if they will understand the gravity of their actions. Society understands that young people can commit horrific actions. Yet, when their brain matures, they understand what they have done, and actually have the reasoning power to see the error of their ways, feel regret, and strike to make amends. Therefore, it is unfair for juveniles to be tried as adults because, until their brains are fully developed, they are too emotionally immature to be responsible for their criminal actions in the same way as adults.
Although juveniles have underdeveloped brains, a young offender has very little to fear if their sentence is much more lenient compared to an adult’s. Juveniles may be involved in all kinds of crime, ranging from drug sales and possession, burglary, theft, and auto theft. The legal system must be concerned about juveniles having no fear of any consequences. Juveniles should also not be permitted to escape their pasts quite so easily. They should be made to suffer consequences serious enough to prevent them from committing an even more serious crime one day. Therefore, juveniles should be tried as adults, so they do not commit serious crimes again in the future and are suitably punished.
[P1] Juveniles have underdeveloped brains. [P2] The front of the brain is the last to develop, and this deals with juvenile's understanding of the consequences of actions. [P3] Therefore, while juvenile's brains are still developing, they should not be held accountable for their actions in the same way as adults during the legal process.
Rejecting the premises
[Rejecting P3] Although juveniles have underdeveloped brains, if their sentences are too lenient compared to an adult's, there is nothing to stop them committing crimes in the future.