In most states persons accused of violating the law before they are 18 years of age are under the jurisdiction of the juvenile courts, and persons accused of violating the law when they are 18 years of age or older are under the jurisdiction of the criminal courts. Some states begin prosecuting persons as adults in the criminal court system when they are 17 years of age, and some states begin prosecuting persons as adults in the criminal court system when they are 16 years of age.

But all states have transfer laws that permit or require criminal prosecution of some young offenders—even though they are still of juvenile age, as defined by the state’s laws. Transfer laws vary from state to state, but generally fall within three categories: (1) judicial waiver laws that allow juvenile courts to waive jurisdiction on a case-by-case basis; (2) prosecutorial discretion or concurrent jurisdiction laws that define a class of cases that may be brought in juvenile court or in criminal court—usually at the discretion of the prosecutor; and (3) statutory exclusion laws that grant criminal courts exclusive jurisdiction over certain classes of cases involving juvenile-age offenders.

The laws that govern when a person of juvenile age may be prosecuted as an adult in the criminal court system are generally located in a state’s statutes.

In New York, individuals who are accused of violating the law are typically under the jurisdiction of the juvenile courts if they are under 18 years of age. However, New York has provisions for prosecuting juveniles as adults under certain circumstances. These provisions are in line with the three categories of transfer laws mentioned: judicial waiver, prosecutorial discretion, and statutory exclusion. Judicial waiver allows juvenile courts to transfer a case to adult court after considering factors such as the seriousness of the offense and the juvenile's history. Prosecutorial discretion gives prosecutors the choice to file charges in either juvenile or criminal court for certain offenses. Statutory exclusion laws in New York automatically exclude certain serious offenses from juvenile court jurisdiction, meaning those cases are directly filed in the adult criminal court system. The specific age at which a juvenile can be tried as an adult and the types of offenses that trigger these provisions are detailed in New York's penal code and family court act.