When lawyers were preparing to defend against a lawsuit over a death in police custody in Fresno, California, they knew whom to call.
Over the past two decades, Dr. Gary Vilke has established himself as a leading expert witness by repeatedly asserting that police techniques such as facedown restraints, stun gun shocks and some neck holds did not kill people.
Officers in Fresno had handcuffed 41-year-old Joseph Perez and, holding him facedown on the ground, put a spinal board from an ambulance on his back as he cried out for help. One officer sat on the board as they strapped him to it. The county medical examiner ruled his death, in May 2017, a homicide by asphyxiation.
Vilke, who was hired by the ambulance provider, charged $500 an hour and provided a different determination. He wrote in a report filed with the court last July that Perez had died from methamphetamine use, heart disease and the exertion of his struggle against the restraints.
Vilke, an emergency medicine doctor in San Diego, is an integral part of a small but influential cadre of scientists, lawyers, physicians and other police experts whose research and testimony is almost always used to absolve officers of blame for deaths, according to a review of hundreds of research papers and more than 25,000 pages of court documents, as well as interviews with nearly three dozen people with knowledge of the deaths or the research.
Their views infuriate many prosecutors, plaintiff lawyers, medical experts and relatives of the dead, who accuse them of slanting science, ignoring inconvenient facts and dangerously emboldening police officers to act aggressively.
The experts also intersect with law-enforcement-friendly companies that train police officers, write police policies and lend authority to studies rebutting concerns about police use of force.
Together they form what often amounts to a cottage industry of exoneration. The dozen or so individuals and companies have collected millions of dollars over the past decade, much of it in fees that are largely underwritten by taxpayers.
Many of the experts also have ties to Axon, maker of the Taser: A lawyer for the company, for example, was an early sponsor of the Institute for the Prevention of In-Custody Deaths, a commercial undertaking that is among the police-friendly entities.
The New York Times identified over 100 instances of in-custody deaths or life-threatening injuries from the past 15 years in which experts in the network were hired to defend the police. The cases were nearly all lawsuits. About two-thirds of the cases were settled out of court; of the 28 decided by judges or juries, 16 had outcomes favoring the police. (Some cases are pending.)
Beyond the courtroom, the individuals and businesses have offered instruction to thousands of police officers and medical examiners, whose cause-of-death rulings often help determine legal culpability. Lexipol, a Texas-based business whose webinars and publications have included experts from the network, boasts that it helped write policy manuals for 6,300 police departments, sometimes suggesting standards for officers’ conduct that reduce legal liability. A company spokesperson said it did not rely on the researchers in making its policies.
Some researchers and doctors in this ecosystem who responded to questions from the Times said they did not assist law enforcement but provided unbiased results of scientific research and opinions based on the facts of each case. Several pointed to research demonstrating that police struggles overall have an exceedingly low risk of death. They also highlighted health issues that could cause deaths in such circumstances, including drug use, obesity, psychological disturbances and genetic mutations that may predispose people to heart problems.
“Sensationalism, without offering scientifically demonstrated better control techniques, adds no benefit, and merely exacerbates the existing tensions between law enforcement and the society at large,” said Mark Kroll, a biomedical engineer who has backed the idea of an “arrest-related death syndrome” as an explanation of the deaths.
Others in the network, including Vilke, said it was wrong to characterize their work as favoring the police, and suggested the Times’ analysis misrepresented it. “I would disagree,” Vilke said when the Times shared its findings with him. Another of the experts, Dr. Steven Karch, sent papers suggesting Black males and people exerting themselves were generally more likely to have sudden cardiac death.
Lawyers for Derek Chauvin, the former Minneapolis police officer who was ultimately convicted in last year’s murder of George Floyd, also drew upon the same network of researchers and experts. In particular, they turned to the defense of prone restraint, a technique in which officers subdue subjects facedown, as happened to Floyd. The work of Kroll, who has a doctorate in electrical engineering but no medical degree, was cited by the Chauvin defense as proof that putting body weight on someone facedown does not cause asphyxia.
According to court documents, Perez had recently taken methamphetamines when police saw him behaving erratically. They handcuffed and tried to calm him, at one point putting a towel under him to keep him from injuring his face.
After an ambulance arrived, they placed a backboard on top of him and an officer sat on it. In a deposition, the officer said he had been trained that doing so posed no danger of asphyxia. A captain from the department said in the case that the training had relied on an article by Kroll.
“The problem is that when officers get sued in these cases,” said Neil Gehlawat, the lawyer for Perez’s family, the cadre of researchers insist that “‘no one can die this way,’ and then officers start to believe it.”
Shaping the science
The physicians, scientists and researchers who come to the defense of law enforcement officers often cite experiments conducted on volunteers. They shock them with Tasers, douse them with pepper-spray or restrain them facedown on the ground.
Their published findings are usually the same: that there is no evidence that the actions have enough of an effect to cause death.
A Times analysis of more than 230 scientific papers in the National Library of Medicine database published since the 1980s showed those conclusions to be significantly different from those published by others, including studies about restraints, body position and excited delirium.
Nearly three-quarters of the studies that included at least one author in the network supported the idea that restraint techniques were safe or that the deaths of people who had been restrained were caused by health problems. Only about a quarter of the studies that did not involve anyone from the network backed that conclusion. More commonly, the other studies said some restraint techniques increased the risk of death, if only by a small amount.
Vilke’s first report on police restraint was funded by a $33,900 grant from San Diego County during a lawsuit over the 1994 death of Daniel Price. A woman reported seeing odd behavior from Price, 37, who had taken methamphetamines; officers restrained him facedown, his hands and feet tied together.
As part of their research, Vilke and others hogtied healthy volunteers. They observed that measurements of their lung functions decreased by up to 23%, which they concluded was not clinically significant because similar levels of diminished lung capacity could still be considered normal. The judge in the Price case cited the research when he dismissed the lawsuit.
The study and others have been challenged by some scholars and physicians because they are based on controlled conditions that are unlike real life, said Justin Feldman, a social epidemiologist at Harvard University who studies patterns of deaths in law enforcement custody.
“There’s a fundamental problem in terms of study design,” he said. “They’re not using people with more severe mental and physical disabilities. They’re not doing it with people who have taken drugs. When they’re testing Tasers, they aren’t using them as many times as you might see in some deaths.”
When their studies appeared in peer-reviewed publications, the network of experts acknowledged that their work had limitations. But when discussing the research in court, or during trainings and elsewhere, some of them used more expansive language, did not mention conflicting work, or said they had fully refuted scholars who disagreed.
A network forms
Dr. Charles Wetli, a former Miami medical examiner who died last year, was among the first to publish research that launched what has become an industry of sorts defending police officers. He wrote in the 1980s about men who had taken cocaine and died, many while being subdued by the police. He attributed the deaths to a condition he called excited delirium, when someone becomes aggressive from a mental illness or psychoactive drugs.
Later, in 1994, two former law enforcement officers, Michael A. Brave and John G. Peters Jr., described in a paper what they called custody death syndrome. The condition, they wrote, had “no apparent detectable anatomical cause” but could be associated with excited delirium or other vague diagnoses.
In describing the death of a hypothetical suspect, they focused on potential liability: “You immediately cringe at the thought of the critical scrutiny you will soon be facing by the media, by council officials and by special interest groups,” they wrote.
The two men later became affiliated with both the Institute for the Prevention of In-Custody Deaths and Americans for Effective Law Enforcement, another group that provides legal resources for officers. Brave also became a lawyer for Taser.
In an interview, Peters said he founded the Prevention of In-Custody Deaths in 2005 because so many deaths were being blamed on Tasers, which he characterized as one of many misguided criticisms of police conduct. The institute conducts research and training that often rebuts the criticism and is one of several commercial forums that draw like-minded researchers about law enforcement behavior.
Taser provided some early funding to the institute in exchange for training programs, Peters said, and one of its initial sponsors was Brave, who joined Taser’s legal department around the same time.
The business of supporting law enforcement can be lucrative. Not all of the researchers testify frequently in court, but when they do, experts associated with the network typically earn $500 to $1,000 an hour for testimony and depositions.
The Times found that, with rare exceptions, when members of this network weigh in on a case in court, they side with the police.
And assessing the effectiveness of the opinions exonerating the police is difficult because most cases settle or are decided without explanation.
But several cases reviewed by the Times suggest that the research has had far-reaching effects — influencing investigator decisions in death inquests and giving officers assurance that their methods are safe. Some of the experts’ legal statements and educational materials they have prepared for police called safety warnings by Taser and other law enforcement groups outdated or needlessly conservative.
In a deposition in April, the sheriff in Riverside County, California, cited studies backed by the law-enforcement-leaning experts to explain why his deputies held people facedown after handcuffing them. The sheriff, Chad Bianco, described the position as “the absolute safest place for any subject.”
Two years ago, deputies working for Bianco found Kevin Niedzialek, 34, bleeding from a head wound and behaving strangely after taking methamphetamines. They shocked him twice with a Taser, and held him facedown.
When they rolled him onto his back, Niedzialek was unresponsive. He died the next day.