MUNISING, Mich. (AP) — The Michigan Court of Appeals ruled in favor of an Upper Peninsula teenager in a dispute over a school threat and the right to remain silent when questioned by police in the principal’s office.

Authorities in Alger County can’t use the boy’s incriminating statements against him because he wasn’t given a Miranda warning, the court said in a 3-0 opinion last week.

The court said the case broke new ground in Michigan: It could not find a legal precedent that “substantively addressed the situation” in Munising.

In 2021, a 13-year-old boy was pulled from class and taken to the principal’s office at Munising Middle/High School. The boy acknowledged appearing in a video with a shotgun and text that said “be ready tmrw,” a reference to tomorrow.

The boy said he was joking about a school shooting, though the prosecutor charged him with two crimes.

The appeals court affirmed a decision by a local judge who said the teen should have been given a Miranda warning. Miranda is shorthand for the U.S. Supreme Court ruling that gives crime suspects a right to remain silent and consult a lawyer.

The Munising teen wasn’t under arrest. But he was in the principal’s office facing the local police chief with the door closed, the appeals court noted, conditions that could be interpreted as a “custodial interrogation.” The boy’s father was also present.

The teen was “questioned by law enforcement in an environment and under circumstances suggesting he was not free to leave, and he was never told that he could leave at any time,” Chief Judge Elizabeth Gleicher wrote.

The case will return to Alger County unless prosecutors ask the state Supreme Court to consider accepting an appeal.