Oakley man guilty of murdering romantic rival on Valentine’s Day, faces life without parole

Jose Quintanilla, 27, was convicted of murdering 21-year-old David Olivares, a Brentwood resident who Quintanilla had accused of sleeping with his wife.

MARTINEZ — After two full days of deliberation, a Contra Costa jury convicted an Oakley man of murdering a 21-year-old over jealousy on Valentine’s Day 2020.

Jose Quintanilla, 27, was convicted Friday of first degree murder, an enhancement for lying in wait, and another enhancement for personal use of a firearm. Prosecutors say he plotted with co-defendants Sabrina Glenn and Angel Rodriguez to set up the victim, Brentwood resident David Olivares, based on a belief that Olivares had sex with Quintanilla’s wife.

During trial, Quintanilla’s lawyers asked the jury to convict him of conspiracy to commit robbery but said Quintanilla had no involvement in any murder plot. Jurors did just the opposite; they convicted Quintanilla of murder but acquitted him of robbing and conspiring to rob Olivares.

Quintanilla allegedly told Glenn that Olivares had sexually assaulted a family member and used another lie to to get Rodriguez on board with the plot, telling them both he intended to rob Olivares. Instead, when Olivares showed up to a Pittsburg park for a date with Glenn on Valentine’s Day 2020, Quintanilla showed with a gun and shot him multiple times, prosecutors say.

Rodriguez, a friend of Quintanilla’s from high school, and Glenn, Quintanilla’s mistress, both testified against him as part of plea deals with Contra Costa prosecutors. The defense hinged on discrediting Rodriguez, who allegedly drove Quintanilla to the park on the night of the murder.

During trial, one of Quintanilla’s lawyers, David Cohen, was hit with accusations by the state bar of misconduct by allegedly cheating clients out of hundreds of thousands of dollars. Cohen has vehemently denied the accusations and jurors were never asked if they learned of them.

After Rodriguez and Quintanilla were arrested, police placed them in a van together that had been equipped with a secret listening device. It captured Quintanilla aggressively questioning Rodriguez if he’d made any admissions to police. Rodriguez eventually answered in an embarrassed tone that he had.

“Because if you did, we’re f—-d, man,” Quintanilla said on the recording. His sentencing date has been set for March 8, 2024.