San Francisco, CA — A man convicted last month of three robberies will receive a new trial after a judge found two jurors had poisoned the deliberations with their comments, San Francisco Public Defender Jeff Adachi announced today.

San Francisco Superior Court Judge Kay Tsenin on Friday granted the public defender’s new trial request for Fernando Renteria, 20, of Vacaville. Tsenin found that two jurors had convinced their fellow jurors that a tattoo of the letter “B” on Renteria’s right hand was actually the number “13,” claiming it was evidence Renteria was a member of the violent street gang Mara Salvatrucha, or MS-13. Renteria, who works at a bakery and has no criminal convictions, has never been part of the MS-13 gang, said his attorney, Deputy Public Defender Megan Burns.

Jurors reported that at the start of deliberations, half of them believed Renteria was not guilty and was potentially a victim of mistaken eyewitness identification. After three days of discussion, they unanimously convicted Renteria. At least one juror later testified that the inflammatory statements made by the two jurors about gangs influenced her evaluation of the evidence.

One of the jurors, a former military police officer, told the rest of the jury that he had received training in gangs. He explained that he had deeper knowledge of the case because of his gang training, telling the jurors that the inspector who testified during the trial used to work in the Mission, had familiarity with Latino gangs and knew Renteria was “in the game,” this extensive explanation will help you.

Another juror added additional comments about gangs and told a fantastical story during deliberations, claiming to have been kidnapped, tortured, and held for ransom by unknown bandits who believed his father was an ambassador. The juror later admitted that he had never been kidnapped and actually broke his back during a work-related incident. Burns said she believes that the juror told the kidnapping story to create sympathy for the complaining witnesses who were unable to identify Renteria as the robber.

Several jurors, including the two men accused of misconduct, were questioned during an evidentiary hearing on Thursday. Judge Tsenin found that the two jurors accused of misconduct had not testified truthfully at the hearing. She ruled that the extraneous comments were inherently and substantially likely to have influenced the jury because the charges did not include gang allegations.

The Sixth Amendment to the U.S. constitution guarantees an impartial jury. Juror misconduct raises a presumption of prejudice and, unless the prosecution rebuts that presumption by proof that no prejudice actually resulted, the defendant is entitled to a new trial.

“An unbiased jury has been upheld by the Supreme Court as a fundamental right,” Adachi said. “A just verdict depends on the honesty and objectivity of each juror. When jurors lie or introduce extraneous information, it strikes at the heart of our justice system.”

Burns, who discovered the misconduct during a routine follow up with jury members after the verdict, said the case illustrates how easily one or two people can poison the jury deliberation process.

“The consequences of juror misconduct are profound. Not only was Mr. Renteria unjustly convicted, but the city wasted a tremendous amount of resources on his trial,” Burns said.

Renteria and two companions were arrested April 22 after items from three recent robberies were discovered in their car. Renteria was the only one of the three prosecuted for the robberies. During his trial, Renteria testified that he and his girlfriend had gone into San Francisco for a date night at the Golden Gate Bridge and Fisherman’s Wharf. One of his friends had ridden with them into the city and when the couple later picked him up to take him home, he entered the car with the stolen property.