‘Officials Knew, None Acted’: Yolo County Grand Jury releases report on deadly Esparto explosion

More than eight months after a deadly explosion rocked the small Yolo County town of Esparto, a new grand jury report says systemic inaction and failures led to disaster.

The damning 32-page report titled “Esparto Fireworks Explosion: Officials Knew, None Acted” was released Thursday. 

It outlines how county supervisors, the sheriff’s office, local fire departments and others missed previous tips and information that could have prevented the July 1, 2025 explosion that instantly killed seven workers and started the 78-acre Oakdale Fire.

Findings

Yolo County ordinances have banned fireworks businesses anywhere in the county since 2001, including in unincorporated areas as of a June 2025 amendment. County officials previously said the property where the fireworks facility was located, at the crossroads of County Roads 86 and 23, is zoned for agriculture and prohibits the storage or handling of fireworks or explosives.

However, the grand jury said county officials and leaders failed to act, and that enforcement could have prevented death and destruction. 

“It was pretty clear in county ordinances that this sort of activity is not permitted, and yet lots of people knew about it and no one stepped forward to say that this has to stop,” said grand jury foreperson Richard Zeiger.

County supervisors acknowledged last August some staff members within the county’s building division had known fireworks were being stored on site years before the disaster. This came as a new agricultural storage building was being built on the property in mid-2022.

The report said county staff received a tip that two pyrotechnic businesses were operating on site in June 2022. Officials also conducted a site visit that month, and were reportedly told by Esparto fire officials the businesses were approved by the federal Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF). Building officials also reported both “safe and sane” and more dangerous fireworks were stored in containers on site.

Aerial photographs taken February 2022, November 2023 and June 2024 of the Esparto property where the fireworks facility was located. The construction of the new building is seen in the lower right of each image, along with added storage containers.Google Earth

The Yolo County Community Services Department then took steps toward possible enforcement, but the grand jury said email conversations about the site “abruptly ceased” within days and no action was taken. 

County officials reportedly did not check with state or federal agencies about whether they were monitoring the pyrotechnic companies, and the grand jury said there is no record Cal Fire ever inspected the property.

The grand jury also said testimony indicated the Board of Supervisors had “given code enforcement a low priority,” repeatedly rejected efforts to boost enforcement and “fostered a culture of tolerance for code violations.”

“Yolo County, probably like a lot of rural counties in the state, has this sort of attitude that farmers should have fairly broad control over their property… they should be given a fair amount of leeway,” Zeiger said. “This just turned out to be a really bad example of the consequences of that sort of approach.”

Other findings included a lack of resources and training among local fire districts and county departments that impacted fire prevention and code enforcement.

The Yolo County Sheriff’s Office also failed to enforce existing fireworks ordinances, according to the grand jury. The department also did not adequately review documented outside employment by sworn officers, or provide enough training.

Potential changes

The grand jury acknowledged it is one of multiple bodies looking into the Esparto explosion. Cal Fire’s Office of the State Fire Marshal turned over its investigation findings last month to the Yolo County District Attorney’s Office. Fire officials said their report included “evidence of illegal activities,” though no further information was provided.

The grand jury can investigate misconduct by public officers but said it has not yet opened a full investigation into any individual “because of the ongoing nature of other investigations.” However the group said it reserves the right to launch one if circumstances change. 

Among its recommendations, the report suggested county supervisors establish a Yolo County Fire Warden position, as well as improve training and monitoring systems.

The report also suggests the Yolo County Sheriff’s Office review outside employment policies for its employees, among other measures.

Read the full report here:

Yolo County responds

In a statement published Thursday, county officials say they "respectfully disagree” with the grand jury’s suggestion that the county did not prioritize code enforcement.

“While funding levels have varied historically, the Board has consistently supported and funded the County’s code enforcement program in recent (compared to previous) years and continues to recognize the essential role it plays in protecting community health and safety,” the statement read.

The county said it has started internal reviews of processes including code enforcement, and “continues to work closely with local fire agencies and regional partners to strengthen coordination and communication.”

Yolo County said the civil grand jury’s findings and recommendations “are administrative in nature and should not be confused with criminal investigations or potential charges, which are handled separately.” The county has 90 days to respond to the report.

A spokesperson for the Yolo County District Attorney’s Office declined to comment, citing an ongoing investigation. CapRadio has reached out to the Yolo County Sheriff’s Office for comment as well. 

“There needs to be a sort of a change in attitude from the highest level,” Zeiger said. “If you're not enforcing codes appropriately, there can be consequences down the line that you don't even see.”

History of the property

The land where the fireworks storage facility sat was previously owned by Jerry Matsumura, a longtime Esparto resident, farmer and a fire commissioner with the Esparto Fire Protection District. 

The grand jury’s report said Matsumura was also an active member of the Western Pyrotechnic Association, and was known for putting on fireworks displays around the July 4 holiday and in the fall. The grand jury described fireworks as Matsumura’s “sideline, somewhere between an actual business and a hobby.”

The report also identified one of his former business partners as Kenneth Chee, the owner of Devastating Pyrotechnics. This was one of two companies operating out of the Esparto facility when it exploded.

After Matsumura’s death in 2015 the property was passed down to his daughters Reiko Matsumura and Tammy Machado, both of whom were employees of the Yolo County Sheriff’s Office at the time of the explosion. 

Tammy Machado’s husband Sam Machado is also a Sheriff’s Office Lieutenant. The grand jury report determined he “failed to obtain the required prior approval from the Sheriff for his financial interest in the fireworks business on his property.”

The Machados were put on leave following the incident. Reiko Matsumura was placed on unrelated disability leave before the July 1 explosion and retired in September 2025.

Law enforcement and prior knowledge

Yolo County Chief Building Official Scott Doolittle noted in a June 2, 2022 email the connection between the storage site and law enforcement, saying he received a “tip” about the property being used to run a pyrotechnics business. 

The grand jury report also noted officials said in these email exchanges they would “tread lightly.”

“Sheriff deputies, potentially including deputies we work with, are reported to be involved in the business,” Doolittle wrote. “They are using an ag exempt building plus 25 Conex boxes for the operation.”

Zeiger said code enforcement officials rely on the assistance of sheriff’s deputies, a relationship that can impact decision-making. “That can create difficulties if these are the same people that are helping you day in and day out and now there may be a problem on their property,” he said. 

Doolittle also said Esparto Fire Protection Chief Curtis Lawrence “confirmed that the pyrotechnic business is licensed through the federal ATF.” The second company located on the Esparto site, Blackstar Fireworks, is owned by Craig Cutright — a volunteer firefighter with the Esparto Fire Protection District. 

Cutright is identified in the report as having contacted county officials in 2021 about setting up a new fireworks business on a nearby property. The grand jury said there is no evidence county officials told him fireworks businesses are illegal.

Chee had previously been denied a license from the ATF following a criminal conviction in the 1990s that made him ineligible to receive or possess explosive materials.

Continued reckoning

Cutright and Chee had their pyrotechnic licenses suspended and later revoked by Cal Fire for violating California’s laws and regulations.

In December the California Division of Occupational Safety and Health (Cal/OSHA) issued 15 citations to Devastating Pyrotechnics and its successors, totaling $221,000 in fines. 

Cal Fire has also carried out enforcement actions across California in connection to the Esparto disaster. But the agency has also faced scrutiny and criticism over whether it is adequately enforcing the state’s fireworks laws or whether the illegal pyrotechnics in Esparto could have been detected sooner. 

The Sacramento Bee found that a Cal Fire raid of a fireworks facility in the southern California city of Commerce last May was based on a search warrant connected to Devastating Pyrotechnics. The raid seized over 100,000 pounds of illegal pyrotechnics.

Officers from Cal Fire and the Bureau of Alcohol, Tobacco, Firearms, and Explosives (ATF) with seized fireworks following a raid in Commerce May 21, 2025. Cal Fire says the raid seized over 100,000 pounds of illegal fireworks.Courtesy of Cal Fire Office of the State Fire Marshal

Another Bee investigation found Devastating Pyrotechnics tried to claw back fireworks seized in Commerce, citing close ties with the Yolo County Sheriff’s Office.

At least one state lawmaker has taken steps to strengthen oversight and close state loopholes. 

Yolo County State Senator Christopher Cabaldon’s Senate Bill 828 would require anyone who holds or applies for a pyrotechnics license to disclose the full address of the fireworks storage location to local authorities and the State Fire Marshal’s office, which would undergo annual local and state inspections. The bill would also bar any person who committed a violent crime from being licensed. 

What comes next remains to be seen, but Zeiger said the tragedy has left an enormous impact on the community. 

“People heard it and saw it all over the county, I don't think there's any question that it was a terrible thing,” he said. “It's a tragedy of no small amount.”