An Oakley man allegedly set up and killed romantic rival on Valentine’s Day. Now his high school friend and mistress will take the stand against him

Jose Quintanilla, 27, allegedly used his mistress to set up 21-year-old David Olivares for a date in at a Pittsburg park, then showed up instead and shot him seven times.

MARTINEZ — A 27-year-old Oakley man is before a jury facing charges that he murdered a romantic rival on Valentine’s Day, after arranging for his mistress to set up the victim by messaging him on Instagram and arranging an evening rendezvous.

Jose Quintanilla is charged with murder and conspiracy in the death of 21-year-old David Olivares, a Brentwood resident who Quintanilla had accused of sleeping with his wife, according to prosecutors. As a result, Quintanilla allegedly plotted to set up and kill Olivares, arranging for 24-year-old Sabrina Glenn to set up a meeting at Woodland Hills Park in Pittsburg, and getting a ride to the park from his high school friend, 24-year-old Angel Rodriguez.

“(Olivares) thought he was going to have a first date on Valentine’s Day,” Deputy District Attorney Kevin Bell told jurors in his opening statement on Monday. “Little did he know he was minutes away from being murdered.”

The defense does not deny the existence of a criminal plot, but will argue that Quintanilla planned a robbery, not a murder, and that the prosecution can’t even place him at the park when Olivares died. A lot of that evidence will hinge on the word of Rodriguez, who — like Glenn — has agreed to testify against Quintanilla in exchange for leniency.

“The prosecution’s case is a house of cards,” defense lawyer Alexander Guilmartin told the jury, adding that it all hinged on Rodriguez, “a witness who cannot be trusted.”

In his presentation, Bell went through the cast of characters who will play a key role in the trial. Quintanilla, he said, was motivated by jealousy, and had accused Olivares in a social media message of “sleeping with my b—-,” meaning Quintanilla’s wife.

Next up was Quintanilla’s mistress, Glenn, who worked as an exotic dancer at the time. Bell showed the jury pictures of the young woman wearing a g-string and posed provocatively, then said Quintanilla had “manipulated” her into feigning a romantic interest in Olivares, by coming up with a story that Olivares had sexually assaulted Quintanilla’s family member.

Angel Rodriguez, said Bell, was brought into the plot in part because he owed Quintanilla $200 for marijuana. He later told police that Quintanilla had said he intended only to rob Olivares, and that Rodriguez had no idea that Quintanilla was even armed when he gave him a ride to the park.

Both Rodriguez and Glenn have accepted plea deals for lesser crimes, robbery and assault, respectively, and it will be up to Judge John Kennedy to sentence them after the trial’s over. Guilmartin said that Rodriguez is the lone witness who claims Quintanilla was at the park, but that those statements were a “desperate” attempt to “cover his butt” after a SWAT team raided his Brentwood home and brought him to a Pittsburg police station for questioning.

“As he sat in that patrol car, he had a lot of time to think about what he wanted to say,” Guilmartin told jurors Monday.

But there’s another piece of evidence jurors will hear: Quintanilla’s own words, spoken as he and Rodriguez sat in the back of a police van that had been secretly equipped with a listening device. Upon laying eyes on Rodriguez, Quintanilla begins to aggressively question him, demanding to know whether he answered police questions.

“Because if you did, we’re f—-d, man,” Quintanilla says on the recording.