More than two years after a deadly family confrontation in Simi Valley, Gerardo Arroyo Almanza has pleaded guilty to killing his father and threatening other relatives. The plea, announced Monday, brings a new legal chapter to a case that began with family members trying to check on his well-being.
According to an August 3 release from the Ventura County District Attorney’s Office, Almanza pleaded guilty to second-degree murder in the death of Alfredo Arroyo Sancen and to three counts of criminal threats against additional family members. He also admitted using a deadly weapon and having a prior strike offense.
Family Welfare Check Turned Deadly
Prosecutors say several relatives went to Almanza’s Simi Valley residence on April 6, 2024, to check on him. The account says he came out with a knife, threatened to kill family members, chased his parents around a parked car, then pinned his father to the ground and stabbed him several times.
An EMT-trained neighbor provided first aid before Sancen was taken to Los Robles Regional Medical Center, where he died, according to the DA’s office. A contemporaneous report republished by Yahoo News identified Sancen as 71 and said police arrested Almanza a block away after he fled the scene.
Competency Proceedings Delayed The Case
The case did not move straight from arrest to trial. The DA’s release says a court-appointed mental health expert found Almanza incompetent to stand trial on March 6, 2025, and that he was deemed competent on October 6, 2025.
Sentencing Is Set For September
Almanza is scheduled to be sentenced on September 11, 2026, in Ventura County Superior Court and remains in custody without bail. Prosecutors say he is facing 30 years to life in state prison, plus an additional nine years and four months.
Senior Deputy District Attorney Theresa Pollara, who prosecuted the case for the DA’s Major Crimes Unit, said the guilty plea brings accountability for the killing and the threats against other family members. “Our hope for the family is that they are able to move forward in their healing,” Pollara said.
