California DOJ Bureau of Forensic Services processed crime scene and evidence the refuted killer’s story
“This case is an example of the exemplary work done by California DOJ criminalists to shed light on what really happened versus what a suspect is telling investigators. When there are no witnesses to a murder, these criminalists become the eyes and ears of the victim.”
– CSLEA President Alan Barcelona
OROVILLE – On September 9, 2025, Jessica Rose Nichols, 27, of Oroville, was sentenced to serve 25 years to life plus 10 years, after admitting in August that she executed her husband in their Oroville residence in 2020.
On August 7, 2025, Nichols pleaded no contest to first-degree murder and admitted to using a firearm to commit a crime. In the early morning of November 6, 2020, Nichols shot her husband, Mateo Lange, 22, three times with a handgun while he slept on the living room floor of the residence they shared on Grand Avenue in Oroville.
Family and friends of the victim described him as a gentle giant with a huge smile and a bigger heart, in contradiction to the defense claim that Lange had been physically and emotionally abusive to Nichols and that she had shot him in self-defense.
Supervising Deputy District Attorney Marc Noel reviewed the evidence that would have been presented at trial that contradicted the defendant’s claims of battered woman’s syndrome. Noel explained to the judge that text messages and selfie videos by Nichols showed she, not the husband, was the physically abusive one in the marriage. Specifically, Noel referenced electronic messages in the months preceding the murder in which Nichols claimed to have thrown items at the husband, destroyed his electronics and clothing, and admitted to previously trying to kill him by poisoning his pillow with household cleaner.
Noel also laid out for the judge the forensic evidence that established beyond a doubt that the husband was lying on his back, sleeping at the time he was shot. Specifically, Noel walked the court through the forensic evidence collected at the scene and the audio recording of the shooting.
A neighbor heard the first two shots and walked outside to investigate. That neighbor saw Nichols walk out of the couple’s apartment pushing a baby stroller, which she handed to the neighbor. The stroller contained the couple’s 22-month-old child. Along with the stroller and child, Nichols handed a note to the neighbor, which contained the child’s name and contact info for the child’s paternal grandmother. Nichols then turned and walked back into the couple’s apartment.
At that point, the neighbor called 911 and began speaking with an Oroville police dispatcher. As the neighbor was on the phone with the dispatcher, the neighbor heard a third gunshot from inside the couple’s apartment, which was recorded on the 911 line. Nichols then came out of the apartment and sat down on its front steps to await the arrival of the police. When Oroville Police officers arrived a few minutes later, they found Nichols and a 9mm Glock semi-automatic pistol sitting on the porch. Inside the apartment, the officers found Lange lying mortally wounded on the living room floor on a makeshift bed with multiple gunshot wounds.
Nichols was immediately arrested by responding officers, and the pistol was seized. During a subsequent interview by police detectives, Nichols claimed she shot Lange in self-defense when he charged at her and threatened to injure her during an argument between the two.
Meanwhile, crime scene experts from the California Department of Justice, Bureau of Forensic Services, responded to the apartment to assist police in processing the crime scene and to preserve evidence. Based upon physical and forensic evidence, the crime scene experts determined Lange had been lying on the floor with a blanket covering most of his body and his head on a pillow. They found a bullet hole in the blanket and bullet fragments on and around the pillow, showing that Lange was lying flat on the floor and not up and “charging” when he was shot.
During a subsequent autopsy, a forensic pathologist determined Lange had been shot twice in the head and once in the chest. The pathologist also determined that the chest wound was a “contact” wound, meaning that the gun was very close to the body at the time it was fired.
Also, during the crime scene investigation, Oroville detectives observed a security camera in the front window of the apartment, pointing outward and covering the approach to the front door of the residence. Detectives were able to access the recordings from the camera and determined that the camera had a microphone and had recorded audio of the murder. The audio recording proved that prior to the shots being fired, there was no argument between Nichols and Lange. The audio also showed that after her first shot, Nichols’ gun jammed, and she could be heard quickly clearing the jam, before chambering a new round and firing the second shot. Detectives were also able to review audio from the prior evening from the security camera, and could hear Lange arguing with Nichols, with Lange stating that he intended to leave Nichols the next day and end their marriage.
According to the district attorney, the case was delayed for five years by a variety of defense-related factors. Specifically, Nichols changed attorneys multiple times. More recently, the case was continued multiple times while her current defense attorney attempted to retain a “Battered Woman Syndrome” expert.
