A Solano County Superior Court judge, noting recent changes to state laws about prosecuting minors for serious felonies, ruled Friday that the first-degree murder case against a Vallejo teen will be transferred from adult to juvenile court.

Judge E. Bradley Nelson made his decision in the case against Robert Matthew Cortez, 19, who was charged with the 2015 shooting of a 20-year-old Antioch man in Vallejo.

Cortez appeared in Department 4 with his defense attorney, Edward D. Cohen of Vallejo, for a trial management conference and a motion to dismiss the murder charge.

But after hearing a request from Cohen and counter arguments from a deputy district attorney, Nelson cited a September 2018 law signed by former Gov. Jerry Brown, Senate Bill 1391, eliminating prosecutors’ ability to try a defendant under the age of 16 as an adult. Cortez was 16 at the time of the alleged crime.

Previously, prosecutors could request to transfer 14- and 15-year-olds to adult court if they were charged with a serious felony, such as murder, arson, robbery, rape or kidnapping. Those convicted under the new law must be held in locked juvenile facilities instead of adult prisons.

“Now we go back to juvenile court,” Cohen said during a brief interview after the morning’s proceedings in Department 4 of the Justice Center in Fairfield. He called the judge’s ruling “consistent” with the new law.

But during the proceedings, Nelson alluded to legal challenges to SB 1391 and made his decision in light of the law’s passage and remains in effect, pending a state Supreme Court ruling.

“If it’s ruled constitutional, it (the case) stays in juvenile court,” said Cohen, adding, “If it’s declared unconstitutional, it comes back to adult court.” Cortez had been scheduled for a jury trial to begin Feb. 5.

During the morning’s proceedings, Nelson also did not rule on Cohen’s motion to dismiss the murder charge, saying, “We never even got to that today” and calling it, as he looked directly at Cohen, “a bit of a stretch.”

The case against Cortez involves him and his brother, Lorenzo M. Cortez, 22. They are charged with murder in the Jan. 10, 2015, gunshot slaying of William W. Brown at the Vallejo Regional Education Center, an adult school.

Police records indicate Brown was allegedly shot shortly before 3 p.m. in the 400 block of Del Sur Street and attempted to flee on foot from the two brothers before collapsing on the school campus.

Upon arrival, authorities found the victim’s car running, a single bullet hole apparent, with glass and blood on the ground and inside the vehicle.

A witness, who was nearby in front of his residence working on a lawn mower with a friend, later told police he saw the two men chasing the hobbling victim toward the school. When Brown fell to the ground, the man said he saw the two men standing over him, picking through his pockets, with one of them shooting him before they both ran off through the school property.

A close friend of the victim, who allegedly spoke with Brown in person on the day of the shooting, told police Brown had set up a meeting in Vallejo with Lorenzo Cortez to exchange a gun, according to court records. However, the man said Brown was reluctant about going through with the exchange. At 3:40 p.m., the man told police he received a call from Lorenzo Cortez, who asked him where the victim was. The man said Lorenzo sounded as if he were running while speaking.

During an earlier court proceeding, Nelson ordered the younger Cortez, who was arrested at age 17, to stand trial on the murder charge. If convicted, Cortez , who remains in custody without bail, will not face the possibility of a death sentence.