A Simi Valley man killed his girlfriend while her five children watched.

A Simi Valley man killed his girlfriend while her five children watched.

Ramon Joseph Rivas faces up to 51 years to life in prison after admitting to the stabbing death of Jessica Marie Tinoco.

No child should ever have to see their parent hurt. The trauma left behind in this home will last a lifetime.

On September 27, 2024, police in Simi Valley arrived at a home to find a horrific scene. Ramon Joseph Rivas walked out of the house shirtless and covered in blood.

Inside, officers found Jessica Marie Tinoco with multiple stab wounds. She was taken to a hospital but did not survive her injuries.

Witnesses say the attack happened during an argument. Rivas went to the kitchen, grabbed a steak knife, and attacked Tinoco while her five children were in the room. The children managed to run away as the violence unfolded.

What the evidence shows

• The attack involved a bent steak knife found at the scene.
• Tinoco suffered multiple stab wounds to her face, abdomen, and arms.
• Four of the wounds were determined to be fatal.
• The crime occurred in the presence of the victim's five children.
• Rivas had prior violent felony convictions before this incident.

The bigger question

We often talk about domestic violence as a private matter, but this case shows how quickly it can turn into a public tragedy. When a home becomes a place of fear, how can we better protect those who are most vulnerable?

We should ask why someone with a history of violent conduct was in a position to cause such harm. Are there gaps in our system that fail to flag these risks before they turn deadly?

Rivas has entered a guilty plea to second-degree murder and admitted to several special allegations, including the use of a deadly weapon. By pleading guilty, he has accepted responsibility for his actions, which typically signals that the defense has no viable path to contest the evidence.

What happens now

Rivas is currently held without bail. He is scheduled for sentencing on July 9, 2026, in Ventura County Superior Court.

He faces a maximum sentence of 51 years to life in state prison. This outcome brings a legal end to the case, but the family and the children involved face a long road of healing.

What we still don't know

1. What specific events triggered the argument that led to the stabbing?
2. What support services are being provided to the five children who witnessed the crime?
3. Were there prior reports of domestic violence involving the couple that could have alerted authorities?