The situation with the teen's plea deal was unusual; however, it was done to ensure that he would be incarcerated in a manner appropriate for his needs. A juvenile being charged in adult court is known as a juvenile waiver.
One way this might occur is when a judge in a juvenile court decides to transfer a case to an adult court. By doing this, the juvenile isn't eligible for juvenile protections.
Besides the judicial transfer, there are two other types of waivers that might send juveniles to adult court. One of these occurs when a prosecutor chooses to file a case with both courts, which is known as concurrent jurisdiction. The other is when a charge is subject to a statutory exclusion, which prevents certain charges from being heard in a juvenile court.
For any juvenile who is facing serious charges, the possibility of a juvenile waiver is real. Knowing about these waivers and having representation that can work toward meeting the needs of the juvenile is vital to ensure the juvenile gets the services he or she needs.
Source: FindLaw, "Juvenile "Waiver" (Transfer to Adult Court)" Nov. 26, 2014