VALLEJO — Vallejo Police Det. Jarrett Tonn violated department policy when he fired through the windshield of a still-moving unmarked police truck and struck Sean Monterrosa in the back of the head, according to an 18-month investigation initiated by the department.
A 66-page report produced by the OIR Group — a southern California firm Vallejo officials hired to conduct the investigation — was released after hours Thursday along with a trove of other evidence produced during investigations into the events that unfolded in Vallejo during protests over the police killing of George Floyd in Minneapolis.
The department still has not named Tonn as the shooter. Instead, the city redacted the names of all involved officers in the records released Thursday, despite that their identities have already been widely made public, including in local news outlets and the New Yorker. The Vallejo Police Officers Association filed a petition in Solano County Superior Court to prevent the department from naming Tonn, saying he had received threats. That suit is ongoing.
OIR investigators concluded that Tonn violated department policy for his use of deadly force, which they found was unreasonable. But OIR also found that all three officers in the truck that night did not adequately plan or communicate, which led to a dangerous situation. The other two detectives — Bretton Wagoner and Wesley Pittman — violated policies for not turning on body cameras. All three detectives plus their commander, Capt. Lee Horton, were found to have violated policies for failing to de-escalate the situation and unsatisfactory work performance.
The investigators questioned the three detectives’ decision to drive into the Walgreens parking lot, where approximately 12 people involved in a burglary were present, without a better sense of the danger. Rather than come up with a strategy, they drove toward Monterrosa. Tonn told investigators that he perceived Monterrosa to be a threat because he went to his knees in a “shooting stance,” but they pointed out he could also be surrendering.
Monterrosa was unarmed and shot in the back of the head.
“The additional few seconds it would have taken for the Departmental experts to formulate a sensible, safe, and coordinated plan could have greatly reduced the need for the split-second assessment of Mr. Monterrosa’s intentions that ultimately occurred and would likely have resulted in a different outcome than the officer-involved shooting,” investigators found.
The OIR report also faulted Horton for only briefly communicating with the detectives and not taking the time to come up with a plan. Horton “bears a significant responsibility for this lapse of leadership from one of the highest ranks in the Department,” it said.
Two of the employees found to have violated policies recently left the department. Wagoner left Vallejo police for the Napa County Sheriff’s Office in September. Horton retired a week ago. Tonn and Pittman remain employed in Vallejo, according to the Vallejo Police Officers Association website.
The OIR Group investigation into Monterrosa’s death focused solely on whether the officers violated Vallejo police policy. A criminal investigation into Monterrosa’s shooting from the state Department of Justice is ongoing.
The criminal investigation only began after months of uncertainty regarding who would be responsible for the review of the shooting. Initially, Solano County District Attorney Krishna Abrams sought to recuse herself from the investigation. Shortly after, in a game of political hot potato, then-Attorney General Xavier Becerra also refused to conduct an investigation.
California Attorney General Rob Bonta opened the case shortly after being appointed earlier this year.
In a statement, the police department said it has made “significant changes and improvements” to its code of ethics, use of force policies and procedures, and training in response to the incident. Vallejo Police Chief Shawny Williams said the city is “taking the appropriate steps to ensure that our officers are acting in accordance with the City’s policies and procedures at all times.”
Vallejo police haven’t killed anyone since Tonn killed Monterrosa. It’s a rare desert for a department that’s exceeded national averages. Its officers have been involved in 18 fatal shootings since 2010, which NBC News found was the highest rate in Northern California.
Monterrosa was Tonn’s fourth on-duty shooting since he joined Vallejo police in 2014. All the previous shootings have been found to be within policy.
Investigators found officers planned poorly for an ‘unprecedented’ situation
Following the police murder of George Floyd in Minneapolis last May, protests swept the nation. In the Bay Area, caravans of burglars went from city to city breaking into shuttered businesses, apparently attempting to take advantage of confusion during the unrest and the COVID-19 pandemic.
Hours before Tonn killed Monterrosa, Vallejo and other cities in the Bay Area instituted a rare curfew after learning that several groups had plans to descend upon the city to commit organized burglaries. Despite the curfew, police responded several times to reports of persons looting Walgreens and other businesses across town.
The officers involved in the Monterrosa shooting told investigators the situation on June 2, 2020, was “unprecedented.” They were from the department’s SWAT team but were deployed as patrol to handle the challenges created by mass burglaries at businesses, including at Walgreens.
Just after midnight, police were again dispatched to the Walgreens on Redwood Street after reports said about 12 people were fleeing the property in waiting vehicles. When they pulled into the parking lot, Monterrosa was running toward a black sedan.
Horton met briefly with the three detectives just before they entered the parking lot, but they did not make a plan and the detectives drove in with little understanding of what was happening. Horton broadcasted over police radio channels that, “It looks like they’re armed, possibly armed.” The OIR report found that all three detectives in the truck had “heightened threat perceptions” because of Horton’s broadcast.
Tonn, who was seated in the back seat of the pickup, was holding a SWAT-issued automatic Colt M4 Commando rifle. While the truck was still in motion, he fired it five times through the truck’s windshield.
One of Tonn’s bullets struck Monterrosa, a 22-year-old from San Francisco, in the back of the head, killing him nearly instantly. The gun police thought he had was actually a roofing hammer in the pocket of his black hoodie.
Just after the shooting, Tonn got out of the truck and said, “What did he point at us?” according to body camera video.
“I don’t know, man,” one officer responded.
“Hey, he pointed a gun at us," Tonn yelled back.
Investigators cited Tonn’s initial confusion about whether or not he saw a gun as a reason he did not perceive a reasonable threat.
Later in the night, Tonn reiterated his confusion. “I thought that (expletive) axe was a gun,” he told Horton. “This is not what I needed tonight.”
“I thought he was armed, too. You’ll be alright… You’ve been through this before,” Horton told Tonn.
Tonn later told investigators he saw Monterrosa with his hands near his stomach just before he shot him and took that as an indication that he was armed.
“I had noticed as he was running, in the last few milliseconds of him running, he had his hands up” near his stomach area, Tonn said. “I immediately recognize that's not how normal people run. It was consistent with someone that had something on them.”
New revelations about a drone flying over the shooting scene
Allegations of evidence destruction showed up early in the investigation.
A month after the shooting, then-Vallejo police lieutenants Michael Nichelini and Fabio Rodriguez were placed on paid administrative leave after someone removed the windshield Tonn fired through from the truck. That windshield was ultimately destroyed.
Nichelini — who at the time oversaw the department’s patrol division and continues to serve as president of the Vallejo Police Officers Association — was formally terminated in March 2021 after sending a threatening email to a local journalist and for emailing members of the union an image of a 1906 city police badge which was inscribed with a swastika. Rodriguez was suspended 40 hours without pay for the destruction of the windshield.
Days after the city confirmed the windshield had been destroyed, then-California Attorney General Xavier Becerra said his office would independently investigate the alleged destruction of evidence. The Attorney General’s Office has yet to announce the conclusions of that review.
Vallejo police’s disclosure on Thursday also includes new information about a drone that was flying over the Walgreens at the time of the shooting but it does not resolve questions about what happened to its footage.
The Vallejo Sun previously reported that a U.S. Secret Service expert could not recover any footage from it, yet a drone expert who reviewed the Secret Service report said that it appeared the footage had intentionally been erased.
The drone operator, a Medic Ambulance supervisor, told investigators he witnessed the shooting through the drone’s viewscreen. He said he saw the shots go through the windshield of the truck and then saw Monterrosa collapse. Monterrosa appeared to be running away at the time, he said.
The absence of the drone footage “left the statements of the four VPD officers on scene as the primary evidence of what had occurred,” the OIR Group report stated.
Correction: This article has been updated to clarify that in an interview, Detective Jarrett Tonn said that Sean Monterrosa had his "hands up" but had intended to communicate that his hands were near his stomach area.
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THE VALLEJO SUN NEWSLETTER
Investigative reporting, regular updates, events and more
- Vallejo Police Department
- Sean Monterrosa
- Jarrett Tonn
- Lee Horton
- Bretton Wagoner
- OIR Group
- George Floyd
- Wesley Pittman
- Shawny Williams
- Vallejo Police Officers Association
- Napa County Sheriff’s Office
- California DOJ
- Rob Bonta
- Xavier Becerra
- Krishna Abrams
- Solano County District Attorney's Office
- Michael Nichelini
- Fabio Rodriguez
- U.S. Secret Service
Scott Morris is a journalist based in Oakland who covers policing, protest, civil rights and far-right extremism. His work has been published in ProPublica, the Appeal and Oaklandside.
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