Nicole Pifari and Officer Terry Stangel leaving the courthouse on the first day of his trial for the 2019 beating of Dacari Spiers. Photo by Eleni Balakrishnan

Roger Clark, an expert on police practices and use of force, testified Thursday in the trial against San Francisco Police Officer Terrance Stangel that Stangel and his partner acted counter to their law enforcement training when they rapidly approached and beat unarmed Black man Dacari Spiers in 2019. Clark said both SFPD officers failed to de-escalate the situation, and testified that Stangel’s use of his baton to beat Spiers was wholly unwarranted. 

What Stangel’s defense has characterized as unlawful resistance from Spiers was, in fact, natural confusion to a poorly executed approach by SFPD officers, according to Clark, a retired Los Angeles County sheriff’s deputy and current police-practices consultant. 

Clark was on the stand for about five hours. He was presented as the final witness in the prosecution’s case against Stangel, who is the first on-duty San Francisco police officer in the modern era to be criminally tried for use of excessive force. Stangel beat Spiers, a domestic violence suspect, with a baton on Oct. 6, 2019, breaking two of Spiers’ bones. 

After reviewing the evidence, including body-worn camera footage from both Stangel and Officer Cuauhtémoc Martínez, Clark said it was apparent that Martínez instigated the fateful interaction, and Stangel escalated it. 

“I see [Martínez] as the cause … I see him as the person who provokes it,” Clark said Thursday in court. 

Martínez was shown, in camera footage, jumping out of the police car while Stangel was still parking. Several steps behind, Stangel hurries after Martínez, who is charging toward Spiers and his then-girlfriend, Breonna Richard, who were standing near Beach and Powell streets. 

“That is the moment this thing starts to go south,” Clark told the court. “Martínez has abruptly gone out of the car, left his partner, rushed forward, and there’s nothing criminal going on in front of him.” 

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As he explained the officers’ missteps, Clark pointed to various applicable lessons from the California Peace Officer Standards and Training — standard basic training for law enforcement officers across the state — as well as San Francisco-specific policies. Clark said he has written about 1,300 depositions and given court testimony about 300 times. 

In the body camera footage, which was shown again in court on Thursday, Martínez makes contact with Spiers and Richard, issuing commands to “come over here” as he approaches the apparently confused couple. Within seconds, Martínez tries to grab Spiers’ arm. Spiers pulls his arm away, Martínez and Spiers engage in a scuffle, and seconds later, Stangel has pulled out his baton and is beating Spiers with it. 

Over the course of multiple cross-examinations yesterday, Stangel’s attorney, Nicole Pifari, suggested that Stangel was justifiably using his baton to defend Martínez, who was wrestling with an “assaultive” and resistant subject. 

Clark vehemently disagreed with Pifari’s assessment.  A higher level of force was not necessary, he testified. Since the officers that night didn’t make their intentions clear, Spiers’ “natural” and “instinctive” reactions (backing away, and his movements when being beaten) did not register as resistance in Clark’s eyes. In fact, he said a trained officer would recognize these reactions. 

“It’s obvious here, one officer got one side, you get in and get the other side!” Clark said of how Stangel could have just helped to handcuff Spiers. “We grapple … it’s part of the job.” 

While Clark insisted that Stangel should never have pulled out his baton, he did say that if the weapon had to be drawn, Stangel should have paused and given Spiers a warning, an opportunity to comply or surrender between each of the eight baton swings. 

“When you hear ‘okay, okay,’ and you don’t hear a statement of challenge in terms of aggression,” Clark said Stangel should have stopped. The reactions by Spiers were indications of compliance, he said. What the video showed was a “continuous flurry of beating.” 

But it wasn’t just the beating; the officers’ approach was problematic from the start, Clark testified.

Martínez’s initial “hey you, come here”-type statements, Clark said, are specifically discussed in police officers’ training in terms of what not to do. Clark testified yesterday that such an approach is “considered to be demeaning, objectionable to the person receiving it, especially if they think they haven’t done anything.” 

In police training, Clark said, Martínez’s advance would be presented as having a “very bad outcome” that was foreseeable. 

Further, it is universally accepted by both the prosecution and the defense that no obvious crime was in progress at the moment that Stangel and Martínez arrived, Clark said. Since an in-progress crime or medical needs were not immediately apparent, Clark said an investigative approach should have been used. That would involve communicating why the officers were there and asking questions to look into the domestic violence allegations made in the 911 call minutes earlier. 

Instead, Clark noted that Martínez “goes hands-on within seconds,” without giving Spiers the opportunity to comply, or answering the couple’s questions. 

These issues could have been avoided if the officers had come up with a tactical plan before arriving, another step police are trained to take, Clark said. The two minutes Stangel and Martínez had between receiving the dispatch call and arriving at the scene was plenty of time to review their general strategy, Clark said. 

Martínez said, when he took the witness stand last week, that no plan was verbalized between Stangel and himself. 

Stangel, Clark noted Thursday, had a duty to intervene when Martínez first began acting out of protocol: He could have called Martínez back and ensured they approached the scene together; he could have even sent Martínez back to the car, Clark said. 

Both Stangel and Martínez could have taken steps to avoid the outcome of that night in 2019. Upon questioning from prosecutor Lateef Gray, Clark agreed that police officers are trained to make subjects comply voluntarily, without force, whenever possible. He agreed that when force is used, the least intrusive force option should be applied. 

And, he agreed, police are trained to deescalate encounters with suspects whenever possible. 

Did Stangel and Martínez deescalate? Gray asked. Did they observe their training to use time and distance to avoid a use of force? 

“No. Neither one,” Clark said.  

The prosecution rested its case on Thursday, and the trial will resume on Tuesday with Stangel’s defense. 

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REPORTER. Eleni is our reporter focused on policing in San Francisco. She first moved to the city on a whim nearly 10 years ago, and the Mission has become her home. Follow her on Twitter @miss_elenius.

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  1. Surprise not, that’s why SFPD wanted the investigation
    Austin Tex they have 14 cops for abuse of the use of force pollicy!

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