A 20-year-old Santa Rosa man will be tried at the same time for two murders he's accused of committing a year apart, a judge ruled Tuesday.

Raul Vega is charged in the mistaken-identity killing of Vallejo musician Dewey Tucker during a gang-related drive-by shooting on Interstate 80 in January 2010.

He's also charged with stabbing to death Juan Carlos Angel-Esparza of Santa Rosa during a knife fight on the Kawana Elementary School grounds in January 2011.

Now on the eve of trial, Vega's lawyer sought to sever the cases, arguing they are separate allegations that could prejudice the jury if tried together.

But Judge Dana Simonds agreed with prosecutors that they are both tied to the same Santa Rosa gang rivalry with "cross-admissible" evidence suggesting Vega was attempting to avenge an earlier killing of a friend.

"Both of these cases are first-degree murder cases in which the defendant played a central role in the death of the victims," Simonds said in making her ruling.

Jury selection is expected to begin Friday and opening statements could come Sept. 24. The trial is expected to run one month.

Two former co-defendants have pleaded to lesser charges and a third was acquitted of murder after a separate jury trial. None are expected to testify against Vega.

Instead, prosecutors will rely on Vega's confessions to police.

He's admitted being in the knife fight that killed Angel-Esparza, according to prosecutors and defense attorneys. And he's confessed to driving alongside Tucker's car and firing a handgun at it, according to a CHP officer who testified at Vega's preliminary hearing.

Tucker, who was driving to band practice, died instantly.

Kathy Hernandez, Vega's lawyer, said Vega told police he was acting in self-defense in the Santa Rosa school killing. She said he was unarmed when confronted by Angel-Esparza and managed to wrestle the knife away from him before Angel-Esparza was killed.

But prosecutor Bob Waner argued Vega was looking for trouble when he walked onto the campus, located on rival gang "turf." The two spotted each other, exchanged words and Vega stabbed him in the heart, Waner said.

Waner said both killings are tied to the 2009 slaying of Vega's close friend, Alejandro Ortega, 18, of Santa Rosa. The Angelino Heights gang member is thought to have been shot to death on Moorland Avenue by a rival from Varrio Sureno Locos.

Waner said Vega was among the group of men trying to avenge Ortega's death when Tucker was mistakenly killed. He argued Vega was continuing to seek retribution when Angel-Esparza was stabbed to death.

You can reach Staff Writer Paul Payne at 568-5312 or paul.payne@pressdemocrat.com