That means a hearing set to begin Monday before Hornak will no longer need to address the alleged facts of the case, as anticipated.
Now, Monday's hearing will pertain only to whether the teen should be tried as an adult for the death of Portillo or remain in the juvenile system.
The so-called certification hearing will include testimony related to medical, psychological and psychiatric reports, as well as family or social summary reports. Because that information is protected by juvenile court rules, the certification hearing will be closed to the public and the media.
The teen's attorney, Monte Sleight, said the juvenile system, not adult court, is the appropriate venue for his client.
The crime is punishable by up to five years in prison in the adult system. But if the case remains in the juvenile system, the teen, who turns 18 in October, could be held in detention until he is 21 years old.
"He's a juvenile," Sleight said. "The simple fact is he's a kid. That's what it boils down to."
But Salt Lake County District Attorney Sim Gill's office is seeking to certify the teen as an adult.
"We're trying to balance between a youth who is close to being 18 with the amount of harm that has been caused," Gill has told The Tribune. "You want to balance the status of that youth with the harm that has been caused and the loss that has been suffered by this community."
In a motion to certify the teen as an adult, prosecutors claim the teen is of "sufficient maturity" to be tried in adult court, and that the "likelihood of rehabilitation of the juvenile is minimal." Prosecutors did not elaborate on why rehabilitation might be unsuccessful.
Gill said his staff wants to go through the certification process.
"The goal is to gather information," Gill said. "This is the only avenue that we have to raise the concerns that this individual should really be in the adult system."
Utah law allows certain types of crimes and juvenile offenders to be direct-filed into adult court, but the teen's case does not fit into any of those categories, which is why prosecutors have requested the hearing, Gill said.
Court officials said the teen has never before been to juvenile court on a criminal or delinquency charge.