What Is the Legal Definition of Juvenile Delinquency?

The legal definition of juvenile delinquency is a violation of law committed by a person under eighteen that would be a crime if an adult had done it. That definition comes from federal law at 18 U.S.C. § 5031 and is mirrored, with variations, in every state.¹ The key legal consequence of the label is that a finding of delinquency is treated as a determination of status, not a criminal conviction.² A young person who breaks the law is not a defendant but a juvenile; the proceeding is not a trial but an adjudication hearing; the outcome is not a sentence but a disposition. The system is built around rehabilitation rather than punishment.

The Federal Definition in Two Parts

Federal law splits the definition into two components. A “juvenile” is any person who has not yet turned eighteen. “Juvenile delinquency” is a violation of federal law committed before that eighteenth birthday that would qualify as a crime if an adult did it, along with certain violations of the federal firearms provision that prohibits handgun possession by minors.¹

There is a wrinkle. For proceedings and sentencing, a person can remain classified as a juvenile under federal law until their twenty-first birthday. The federal juvenile system can continue supervising someone past eighteen for offenses they committed as a minor.¹

State definitions follow the same shape. Every state draws a line between juvenile and adult court jurisdiction, and the core idea is identical everywhere: when a person below a certain age commits an act that would be criminal for an adult, the law calls it delinquency and the person a delinquent.

Who the Definition Covers

The upper age of juvenile court jurisdiction is seventeen in nearly every state. As of 2022, forty-nine states and the District of Columbia used that cutoff, meaning the court handles cases involving anyone who was seventeen or younger at the time of the offense. Vermont has set its upper age at nineteen.³

The lower end is far less uniform. Thirty-one states and the District of Columbia set no minimum age at all for filing delinquency charges in juvenile court. Of the nineteen states that do set a floor, the minimum ranges from six to twelve years old.³ Some states route very young children to community services or child welfare agencies instead of charging them with delinquency.

Juvenile courts also do not necessarily lose authority the moment a young person turns eighteen. In most states, the court can keep supervising a disposition past the upper age of original jurisdiction. The most common extended limit is age twenty, used by thirty-four states as of 2019, which lets juvenile court retain authority until the person turns twenty-one. A handful of states extend supervision to twenty-two or twenty-four, and four states allow it to continue for the full term of the disposition order regardless of age.⁴

Two Kinds of Juvenile Offenses

The definition of delinquency splits in practice into two categories, and the law treats them very differently.

Delinquent Acts

A delinquent act is any behavior that would be a crime if committed by an adult. Theft, assault, vandalism, drug possession, and burglary are standard examples. These are the offenses that trigger formal delinquency proceedings and can lead to probation, residential placement, or secure confinement. Serious delinquent acts, such as homicide or armed robbery, can also result in transfer out of the juvenile system entirely.

Status Offenses

Status offenses are acts that are illegal only because of the person’s age. An adult doing the same thing would face no legal consequence. The Office of Juvenile Justice and Delinquency Prevention identifies five main types: truancy, running away from home, curfew violations, underage alcohol use, and ungovernability — behavior a parent or guardian cannot control. Tobacco and other age-restricted activities can also qualify.⁵

Federal law draws a sharp line between the two. Under the Juvenile Justice and Delinquency Prevention Act, one of the core requirements for states receiving federal funding is the deinstitutionalization of status offenders. Juveniles charged with status offenses generally cannot be held in locked detention or correctional facilities. The same law requires that any juvenile held in an adult facility be separated by sight and sound from adult inmates.⁶

Why “Adjudication” Is Not “Conviction”

This is the most consequential piece of the definition and the one most often misunderstood. When a juvenile court finds that a young person committed a delinquent act, the result is an adjudication of delinquency. Federal law explicitly treats that adjudication as a determination of status, not a finding of criminal guilt.² The purpose is to pull the young person out of the ordinary criminal process, avoid the stigma of a prior conviction, and encourage treatment.

In practice, that distinction matters on forms. A person with a juvenile adjudication can generally answer “no” when an employment, college, or financial aid application asks whether they have been convicted of a crime. The FAFSA question about drug convictions, for example, applies only to adult convictions, not juvenile adjudications. The terminology throughout the process reinforces the point. Juveniles face adjudication hearings rather than trials, receive dispositions rather than sentences, and are found delinquent rather than guilty.

The rehabilitation focus runs through everything the court can order. A disposition can include probation, community service, counseling or treatment, restitution to the victim, home confinement, residential placement, or commitment to a secure juvenile facility. Diversion programs can redirect first-time or nonviolent offenders out of formal proceedings entirely, and completing the program usually means the charges are dropped.

When the Definition Stops Applying: Transfer to Adult Court

The protective framing has limits. Every state has some mechanism to move a juvenile’s case into the adult criminal system, and once that happens, the person faces the same penalties any adult defendant would. There are three routes.⁷

Judicial waiver, the most common method, available in forty-seven states and the District of Columbia. A juvenile court judge holds a hearing and decides whether to waive the case to adult court, weighing the severity of the offense, the juvenile’s prior record, their age and maturity, and whether they appear amenable to rehabilitation.⁸
Prosecutorial direct file, in states that let the prosecutor file charges directly in adult court, bypassing the juvenile system.
Statutory exclusion, where state law automatically requires certain offenses, usually the most serious, to be prosecuted in adult court regardless of the defendant’s age.

Even when a juvenile is tried as an adult, the Supreme Court has imposed firm limits. Roper v. Simmons (2005) made the death penalty unconstitutional for anyone who committed their crime before turning eighteen.⁹ Miller v. Alabama (2012) held that mandatory life without parole for juvenile homicide offenders violates the Eighth Amendment; a judge must consider the offender’s youth and individual circumstances before imposing such a sentence.¹⁰ Both rest on the same reasoning: children are constitutionally different from adults for sentencing purposes because they have diminished culpability and greater capacity for change.

What Happens to the Record

A common belief is that juvenile records vanish at eighteen. They do not. Without affirmative steps, a juvenile adjudication stays on record and can surface during background checks for employment, military enlistment, and housing.

Every state offers some path toward limiting access, but the terminology and eligibility rules differ. Expungement destroys the records as if they never existed. Sealing makes them unavailable to the general public while letting law enforcement and courts keep access. Confidentiality laws restrict who can view the records without destroying them.¹¹

Thirty-one states require sealing under specific guidelines, and thirteen states plus the District of Columbia have provisions for expunging juvenile records. In some states the process is automatic once eligibility criteria are met; in others the former juvenile must petition the court and may need to show rehabilitation. Common requirements include reaching a certain age, completing all court-ordered supervision, and having no subsequent criminal convictions.¹¹

Military enlistment is one area where the gap between the law’s promise and real life shows up. Because military branches are federal agencies, they apply their own standards and can access juvenile records even after a state has expunged them. Certain adjudications may disqualify an applicant, though waivers are sometimes available. Colleges and trade schools tend to be less restrictive, and because an adjudication is not a conviction, applicants can usually answer “no” to questions asking about criminal convictions. If a record has been expunged, the applicant can also answer “no” to questions specifically asking about juvenile adjudications. Anyone with a juvenile record should check the sealing and expungement procedures in the state where the adjudication happened, because the window for action and the scope of protection vary a great deal.

1
Office of the Law Revision Counsel. 18 USC 5031 Definitions
2
U.S. Department of Justice. Adjudication As A Juvenile Delinquent
3
Office of Juvenile Justice and Delinquency Prevention. Age Boundaries of the Juvenile Justice System
4
Office of Juvenile Justice and Delinquency Prevention. Extended Age of Juvenile Court Jurisdiction
5
Office of Juvenile Justice and Delinquency Prevention. Status Offenses
6
Office of Juvenile Justice and Delinquency Prevention. Core Requirements
7
Office of Juvenile Justice and Delinquency Prevention. Juvenile Transfer to Criminal Court
8
Office of Juvenile Justice and Delinquency Prevention. Trying Juveniles as Adults in Criminal Court – Transfer Provisions
9
Justia U.S. Supreme Court Center. Roper v Simmons, 543 US 551 (2005)
10
Justia U.S. Supreme Court Center. Miller v Alabama, 567 US 460 (2012)
11
Office of Juvenile Justice and Delinquency Prevention. Expunging Juvenile Records