By Audrey Sawyer and Jack Page
WOODLAND, CA — In the ongoing jury trial of Carlos Dominguez, accused of a 2023 stabbing spree in Davis that left two dead and one injured, three forensic experts testified Tuesday morning at Yolo County Superior Court, providing detailed accounts of DNA evidence, search procedures, and photographs from Dominguez’s home. The trial, presided over by Judge Samuel T. McAdam, has also seen extensive questioning by Deputy District Attorneys Frits P. Van Der Hoek and Matthew Paul De Moura, and cross-examination by Deputy Public Defender Daniel Hutchinson.
Dominguez faces charges of murder, attempted murder, and unlawful use of a deadly weapon.
DNA Analyst Testifies on Blood Evidence and Knife Examination
The morning’s first witness, Heather Tomchick, a criminalist with the California Department of Justice’s Sacramento DNA and Biology Unit, testified about analyzing various items for the presence of blood and DNA.
Tomchick presented several exhibits related to her findings. Exhibits 14A through 14E included swabs from a knife, sweater, towel, bicycle grips, bathroom sink, computer, and tub drain. Reference DNA profiles were also established for victims David Breaux (14E) and Karim Abou Najm (14D). Tomchick confirmed she began examining the knife on June 20, 2023, and identified reddish-brown stains—presumed to be blood—on the blade, handle, and creases of the weapon.
Tomchick used likelihood ratios, a forensic tool to assess the strength of DNA evidence, to explain her conclusions. She testified that a swab from a sweater showed strong support for the inclusion of Dominguez’s DNA. Swabs from the knife indicated a 99% likelihood of Dominguez’s DNA presence and a moderate inclusion for Abou Najm.
When asked by DDA De Moura whether repeated stabbing—such as Breaux being stabbed 31 times—would result in more blood transfer, Tomchick said that many variables, including cleaning, storage, and subsequent handling, could affect DNA presence. She emphasized that she could not determine if the knife had been cleaned.
On redirect, DPD Hutchinson had Tomchick clarify that while she used both the naked eye and a light source during examination, not every stain or crease was swabbed or tested. Some swabs showed mixtures of DNA from up to three individuals, with probability estimates indicating Karim Abou Najm as the primary contributor in one instance and Dominguez as the major contributor in another. Tomchick noted she cannot quantify the exact DNA ratios beyond these statistical probabilities.
FBI Forensic Accountant Describes Home Sketch and Search Process
The second witness, FBI Forensic Accountant Monica Maguire, testified about her participation in the May 2023 search of Dominguez’s home following his arrest. She was tasked with sketching the layout and cataloging items of interest across rooms labeled alphabetically, including Dominguez’s bedroom (Room D) and another room upstairs (Room W).
Maguire described seeing clothing, an iPad, shoes, bedding, and a phone in Room D. While she did not personally photograph or book the items into evidence, she assisted in the process. According to her testimony, items were typically photographed in place before being moved for further documentation or measurement, then returned to their original locations.
DPD Hutchinson asked Maguire whether all rooms in the house were examined and photographed, to which she confirmed the entire home was surveyed—not just Dominguez’s bedroom.
FBI Special Agent John Pope Testifies on Home Entry and Evidence Collection
The third witness was FBI Special Agent John Pope, who specializes in national security investigations. Pope conducted the walk-through of Dominguez’s home during the initial search and took photos upon entry.
In Room D, Pope identified a UC Davis student ID and an El Salvador passport belonging to Dominguez, as well as two phones and an iPad. He noted suspected blood on clothing found in the room, including a rainbow pair of Crocs, shorts, and a T-shirt. Photos (Exhibits #258 and #259) showed a washer, dryer, and cleaning products such as Tide detergent and bleach.
DPD Hutchinson suggested that someone could have used these items to wash away blood, though Pope testified that clothing found in a hamper appeared “soiled” and had not been washed. The hamper contained two articles of clothing soaked in a liquid believed to be blood, along with some blood on the hamper itself.
The FBI handed custody of all evidence over to the Davis Police Department, which was responsible for any further testing. Pope noted that suspected bloody sheets were turned over to the Davis PD, but he was unaware if they were tested.
Previous Testimony Focused on Tent and Knife Found in Grocery Bag
In a prior hearing, FBI Agent Pope also testified about a key piece of evidence: a knife found inside a grocery bag along with items like bread, milk, blueberries, and raspberries. DPD Hutchinson questioned the knife’s placement beneath the groceries, suggesting the defense might argue cross-contamination or mishandling.
Pope also brought a tent to court that he believed matched one found at one of the crime scenes. The Defense alleged Pope failed to bring it earlier due to its “biohazard” status. After a court break to assemble the tent, both sides examined it for cut marks indicating a struggle between the accused and a victim.
The Prosecution and Defense are expected to revisit the tent later in the trial to assess the nature of the attack.
Trial Continues
Testimony is expected to resume Tuesday afternoon, with additional forensic witnesses and analysis of evidence likely to follow.
The Dominguez trial continues to unfold in Woodland Superior Court, drawing significant public interest as testimony reveals increasingly detailed forensic and circumstantial evidence.
