The New Jersey Supreme Court has ordered a new trial for a man serving a 30-year term in the 2013 slaying of a Newark cafe owner, saying police should have read the then-teenage suspect his rights before taking his statement.

The state's highest court on Tuesday reversed the conviction of 24-year-old Zakariyya Ahmad in the slaying of Joseph Flagg in October 2013, NJ.com reported. Authorities said Flagg was a father to four young children who worked as a contractor but ran the Chancellor Avenue breakfast joint on the side and often hired ex-convicts to help.

Authorities said Ahmad, who was 17, was one of three teens who tried to rob the cafe in October 2013. One of the other teens shot Flagg and inadvertently wounded Ahmad, authorities said. The case before the high court centered on Ahmad’s interactions with police after they found him at a hospital with gunshot wounds.

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The state public defender’s office argued that Ahmad was in police custody when investigators prevented him from leaving the hospital with his family. They said he was put in the back of a marked police car and his mother was prevented from driving him home or to the police station herself.

Prosecutors argued that they had other evidence against Ahmad, and at the time of his statement he was viewed as a victim and possibly a witness. But the high court said Ahmad was in custody the moment he left the hospital and should have been read his Miranda rights.

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“At that moment, looking objectively at the totality of the circumstances, it is difficult to conceive that any reasonable 17-year-old in defendant’s position would have felt free to leave; nor did any subsequent events do anything to lessen that impression,” the court said.

Ahmad was sentenced in 2017 to 30 years in state prison on convictions of felony murder and manslaughter as well as robbery and weapons offenses. He is currently incarcerated at Northern State Prison with a parole date in 2043.