I think that if need be, juveniles under the age of 18 should be sentenced to adult prison. If the crime is bad enough, such as if a 15 year old robs and gruesomely kills a man, due to the crime they should be sentenced accordingly to adult prison without alternatives such as juvenile containment or rehabilitation services.
Juveniles should not be sent to an adult prison no matter their crime because it will only make them a worse criminal in the end. Criminals are more likely to reoffend after they have spent time in jail, especially if they are young. According to the National Institute of Justice, the recidivism rate is around 67.8% within the first three years of release. Juveniles should be given a chance to be rehabilitated before they spend years in jail with experienced criminals.
There are many different things one can do in prison if sentenced. There is gleaning and doing your time. Gleaning is when you do things in jail to better yourself such as drug and alcohol counseling, religious groups etc. to improve your overall being. You can also just do your time, where there are many people who have sentences in jail who sit quietly and mind their own business in jail. This leads to no fights or bad behavior which would eventually never lead to a recidivism once they are out of jail. If someone under the age of 18 were to be sentenced to adult jail, it isn't assured they will reoffend once they are out because there are other alternatives once they are in jail. They could even come out better than they were before if their gleaning process works.
It's true there's no way to be positive that juveniles will reoffend after being released, but the chance of it happening increases greatly once they're sent to jail. It would be better if they were sent to a juvenile facility so they can be given what they need. These facilities have education programs, rehab programs, and the ability to be properly re-socialized into a productive member of society. They understand that teenagers make mistakes, and aren't fully able to understand the consequences of their actions. They try and attack the root of the problem, whether that be drugs or a problematic family situation. If juveniles are thrown into adult prison, it will only cause more harm than good. Once some one is tried as an adult, they are tried as an adult for the rest of their life. Sending them to a juvenile facility allows the possibility of expunging their record, and the possibility of a normal life.
Yes, there are many rehabilitation services in a juvenile facility. However, I don't think age plays a factor because if the crime is bad enough, if the intent and execution was absolutely malicious even for a juvenile, they shouldn't be able to go to rehab and then be able to have a normal life after. They should be sentenced to adult jail based on their charges not necessarily age, so if one commits a horrible crime no matter what age they should be sent to adult prison; regardless if they are 13 or 50. It is possible that juveniles don't fully mature until later in life, but it is obvious that maliciously killing or stealing (in some cases) it wrong to do. The fact that the suspect might be 15, should not affect the decision made by a jury or judge because just because they are young doesn't mean that what they did was okay and that they should get special treatment and only go to a juvenile facility, instead of being punished in an adult jail for their crime(s). Therefore, even though they could help themselves with juvenile services, if one commits murder or a crime they must pay their punishment and that should be determined on their charges and sentence regardless of the fact they are under the age of 18.
If a juvenile is sentenced to an adult jail, their sentence will most likely be shorter than if they were sentenced to a juvenile facility. It's a concentrated, intense punishment that may not be appropriate for the crime. Depending on the case it is simply unnecessary for the juvenile to be sent to an adult prison. If it was a status crime, like drinking, they may not deserve a lengthy stay with hardened criminals. Not only will they never be able to get a real job with a record, but they will probably be turned into a criminal, even if they went in an innocent teenager who made a mistake. Now it's true some juveniles deserve to be tried in adult court if the crime is severe enough, but it should vary case by case. It's better to stay on the safer side, and not try juveniles as adults. Adult prisons are also already greatly overcrowded, and do not need another wave of teenage prisoners who may or may not deserve to be there. We have a good alternative already set up, so it would only be common sense to use it.