Force Science News #303:

What do YOU think? Comments sought on PERF call for emphasis

on de-escalation tactics

In this issue:


I. What do YOU think? Comments sought on PERF call for emphasis on de-escalation tactics

II. New study: Another stake in the heart of "positional asphyxia"

III. 2 use-of-force documents that warrant your attention online

IV. And at the upcoming ILEETA conference...


I. What do YOU think?

Comments sought on PERF call for emphasis on de-escalation tactics


A new position paper from the Police Executive Research Forum calls for "all officers" nationwide to be retrained to emphasize de-escalation tactics in their handling of potential use-of-force situations.


The 12-page document offers 30 "Guiding Principles" related to policy, training, tactics, equipment, and public education, some of which already are stirring strong controversy in the law enforcement community.


We'd like to hear your professional opinions and observations on PERF's recommendations.


Email your comments to us at:


Where to read it. The PERF report, which is said to come from two years of "interviews and field research with police chiefs," can be read in full by CLICKING HERE


Among other things, PERF urges that agencies nationwide adopt policies and practices that would:


• Hold officers to a more stringent standard for using force than the "objective reasonableness" test of Graham v. Connor.


• Require officers to "ask themselves, 'How would the general public view' their actions in a threatening encounter.


• Strictly prohibit "shooting at or from a moving vehicle unless someone in the vehicle is using or threatening deadly force by means other than the vehicle itself."


• Explore the use of a Critical Decision-Making Model based on practices in the United Kingdom for determining an appropriate force response.


• "[E]liminate from their policies and training all references to the so-called '21-foot rule'" regarding suspects armed with an edged weapon.


• Train officers that "automatically moving to their firearm" when an electronic control weapon fails is inappropriate.


• Make de-escalation "a core theme" of training.


Applying its recommendations across the board "in a comprehensive manner, and not in a piecemeal or haphazard way," will be costly, PERF says, but will "increase officer safety, as well as the safety of community members."


We're interested in your thoughts and observations. Email us at:


Established in the 1970s as a nonprofit organization, PERF is devoted to "developing national policy guidance and information about best practices in policing," according to a mission statement on its website.


II. New study: Another stake in the heart of "positional asphyxia"


A new study further discredits the persistent claim that restraining a resistant suspect in the prone position risks provoking significant in-custody injuries, including death.


Findings from this latest investigation, focused on actual street encounters, confirm earlier research showing that proning out a combative subject with weight on his back for handcuffing and hobbling does not produce so-called "positional or compression asphyxia," a fatal disruption of respiration.


"Placing violent arrestees in the prone position was shown to be a safe method of control and restraint and is the preferred position for restraining combative arrestees," writes Dr. Darrell Ross, lead author of the study. "[F]rom a risk management assessment,...officers can be confident that when using reasonable force measures, in conjunction with the prone placement of a violent subject, [they] do not create an adverse medical outcome."


Ross, a professor and head of the Dept. of Sociology, Anthropology, and Criminal Justice at Valdosta (GA) State University, was joined in the study by Dr. Michael Hazlett, professor emeritus of law enforcement and justice administration at Western Illinois University.


A full report of their findings, titled "A Prospective Analysis of the Outcomes of Violent Prone Restraint Incidents in Policing," appears in the Forensic Research & Criminology International Journal and can be accessed online free of charge by clicking here


MAKING OF A MYTH. The assertion that prone restraint is "inherently dangerous and contributes to sudden in-custody death" had its origin in laboratory experiments conducted in the last century with healthy volunteers by a medical examiner in Washington State. He theorized that proning out a subject "increased the risk of asphyxia by restricting chest and abdominal movement" and adversely impacting breathing.


Since then, multiple studies employing more modern and sophisticated research methods have "scientifically shown no evidence" that prone positioning poses any enhanced risk of sudden death or serious injury, Ross writes. "The collective medical not support the contention that ventilation is significantly compromised, regardless of being restrained, being restrained hogtied, or placed in a prone position, with or without weight on the back, or restrained and exposed to pepper spray."


In addition, researchers have disputed the theory that "an application of a CEW [to a proned subject] creates an elevated risk of danger," as argued by some activist groups.


Among the studies refuting the medical examiner's old claim was a groundbreaking investigation conducted by Force Science instructor Dr. Christine Hall. Her research team analyzed all arrests involving prone positioning that occurred in a major Canadian city across a recent three-year period and concluded that that tactic "was common and not associated" with arrest-related fatalities.


Yet despite the overwhelming evidence, prone positioning has endured as a perceived hazard. Just last month [Jan., 2016], the autopsy report of an inmate in Colorado who died after being restrained by deputies declared that the death was "a result of complications of positional asphyxia."


BROADER DEMOGRAPHICS. Like Hall, Ross and Hazlett wanted to test the laboratory-created myth against real-world experience. What are the outcomes when officers confront not law-abiding volunteers in a controlled, protected testing environment but "a myriad of persons who are sober, agitated, under the influence of chemical substances, maybe mentally ill" and who must be restrained on the ground or floor because of their violent resistance to arrest?


Whereas Hall concentrated on one municipality, Ross and Hazlett analyzed 1,085 violent prone-restraint incidents in 12 PDs and five sheriff's agencies in six states recorded over a year's period.


Most commonly, the incidents originated as a call for service regarding a disturbance, a mentally ill subject, an assault and battery, domestic violence, warrant service, a suspicious person, or a welfare check.


About 85% of the offenders were male, and their average age was 37. Over 80% were alcohol intoxicated or under the influence of other chemical substances, emotionally distressed, and/or mentally disturbed at the time of their encounter.


Their resistance was coded on a three-level continuum:


• 71% presented "defensive resistance"--"stiffening muscles, pulling or twisting away, or running defeat an officer's attempt of physical control."


• 25% showed "active aggression"--"committing a physical assault against [an] officer by using bodily weapons." Subjects escalated to this level from defensive aggression 44% of the time, with this shift especially prominent among drugged and psychologically stressed individuals.


• 4% committed "aggravated active aggression"--feloniously attacking an officer, "generally using a weapon," which "may result in great bodily harm or the loss of human life."


USE OF FORCE. On average, four officers responded to a given incident, Ross notes, and to establish control and arrest they selected from a dozen force options "beyond using verbal commands" (which were "frequently ignored by the subject"). In nearly 70% of incidents, more than one force measure--the average was seven!--was needed to overcome the resistance.


Empty-hand control techniques were employed in nearly 90% of the incidents, including stuns and strikes in about 20%. Officers used a CEW, usually in probe mode, in 20% of the confrontations, an aerosol in 15%. On average, the CEW was deployed with two trigger pulls, totaling about 10 seconds. "The predominate target" was "the back and back of the shoulder (70%), abdomen/center mass (18%), and legs (12%)," Ross states.


Officers pointed a firearm at a subject without shooting in 2.5% of the incidents. A K-9, a baton, a neck restraint, and/or hogtying were used about 2% of the time.


Once a subject was proned out, the weight of one to three officers was "placed on the person's back to facilitate control and restraint in about 70% of the incidents," Ross writes. A CEW was deployed against an offender who continued to resist on the ground 17% of the time. Mental cases and drug-intoxicated subjects were significantly "more likely to resist in the prone position...frequently requiring officers to apply the hobble restraint" to their ankles, Ross notes.


Overall, about four in 10 suspects continued to resist after being proned and restrained. The total "duration of [an] arrestee being in the prone position" was estimated generally at one to five minutes.


POSITIVE OUTCOMES. As the stats indicate, the events analyzed were often rough-and-tumble affairs, involving considerable struggle and the weight of officers holding subjects down.


Yet, "None of the arrestees died in this study," Ross writes, "and in 80% of the incidents the person did not sustain [any] injury." In 16% of the cases, the arrestee experienced "mild" hurts: a bruise, a cut, marks from a CEW, hyperextension of a wrist or arm, an abrasion, and/or temporary nerve/tissue damage in the wrist.


In only 4% of the incidents did "more significant injury" result: a fracture, a severe strain, laceration, dislocation, abdominal trauma, or K-9 bite marks.


"Arrestees were more likely to sustain any injury when they escalated their resistance [to a level above defensive] and as they continued to resist in the prone position during and after being restrained," Ross explains.


The lack of injury dominated the outcomes at every level of resistance, he writes, and is "significantly associated" with the following force options: "verbal commands; use of a CEW with 2 trigger pulls; 4 or more responding officers; application of empty-hand control techniques; use of an aerosol; weight of the officer applied to the back of the prone arrestee; and the application of handcuffs and the hobble, over a period of 1 to 5 minutes."


A neck restraint, he adds, "was used in only 2% of the aggravated aggression incidents and arrestees did not sustain an injury from its use." Even with hogtying, used in 1% of cases and often blacklisted in law enforcement as a perilous tactic, "the likelihood of sustaining [any] injury remained low."


COMMON & SAFE. In their published report, Ross and Hazlett include a detailed explanation of why the consensus of modern research decisively refutes the alleged threat of positional asphyxia as a risk of prone restraint. Their documented rebuttal includes the debunking of claims that pulmonary function is physiologically jeopardized by the tactic and is further aggravated by the application of OC, CEW discharges, and/or officer weight on the back of a subject.


The results of their study confirm "that the use of the prone position with violent arrestees is a safe restraint method," Ross writes. "Placing a combative person in the prone position occurs numerous times daily throughout the country without the incident resulting in serious injury,...let alone a sudden death."


This has proved true "even when the arrestee vigorously fought and resisted officers' efforts of control and continued to actively resist in the prone position, and after being exposed to varying combinations of force measures."


Given, of course, that it's use is "reasonable" under the circumstances involved, Ross says that officers can feel scientifically "reassured" that they can continue to rely on prone positioning as a valuable option in their use-of-force toolbox.


Dr. Ross can be reached at:


III. 2 use-of-force documents that warrant your attention online


Two informative documents related to use-of-force issues have been posted for free access online by the nonprofit, police training and advocacy group, Americans for Effective Law Enforcement.


1. A 60-page article on police confrontations with armed, violent, and mentally ill subjects. The author, staff editor of the Whittier Law Review, points out that persons with mental afflictions are seven times more likely to come in contact with police and that they often are armed and noncompliant. The explores in details what major court decisions require in terms of law enforcement accommodations for these individuals and offers recommendations for officers on how to safely comply with legal standards.


The article can be accessed by CLICKING HERE


2. An extensive report from NYPD's Inspector General on use-of-force practices in the nation's largest police agency. This was initiated after the controversial arrest-related death of Eric Garner, mislabeled as a "chokehold" victim, in 2014. The report explores force trends, reporting, training, de-escalation instruction, and discipline, with recommendations for improvement.


To access, CLICK HERE


IV. And at the upcoming ILEETA conference...


Addressing another topic, Dr. Ross, along with Atty. Michael Brave and researcher Dr. Mark Kroll, will join in a presentation about investigation protocols for arrest-related deaths on Mar. 16 at the ILEETA [International Law Enforcement Educators & Trainers Assn.] annual training conference in Rosemont, IL.


Theirs is one of a wide array of instructional presentations on human performance and use-of-force issues on tap for the conference. Among those scheduled are:


• Controlling Yourself in High-Performance Scenarios


• Fighting with the OODA Loop


• Tactical Active Threat Response


• Use of Force: Under the Microscope


• Neuroanatomy of Street Survival: Why Physiology Rules


• Black Lives Matter & the War on Police


• De-escalation Strategies


• Human Factors in Training & Performance


• Responding to the Officer Involved Shooting


• Mindset & the Modern Police Trainer


• Reviewing Force on Video


• Legal & Tactical Issues of Police Use of Force.


A number of the conference's 150+ instructors are certified Force Science Analysts.


The conference runs Mar. 13-18 at the Hyatt Regency O'Hare Hotel. ALERT: This year on-site check-in and registration begins at 1400 on Saturday, Mar. 12. Opening ceremonies will be at 0800 on Sunday.


For more information and pre-event registration, CLICK HERE or visit:



© 2017 Force Science Institute Ltd.