ARTICLE 06 · INJURIES IN PHYSICAL ENCOUNTERS
When does someone get injured during a physical encounter?
Knowing that an injury occurred is important. To understand an encounter, however, there is another question: when did it happen?
An injury may occur during an attempt to flee, during a fall, during resistance on the ground, during a struggle to control the arms, during handcuffing, or at another point in the intervention.
The same applies to the officer. An injury may occur before any control technique is used, during an assault, during the approach, during a fall, or while attempting to restrain a person who continues to resist.
Therefore, injury is an important outcome, but the outcome alone does not reconstruct the encounter.
Knowing that an injury occurred does not mean knowing when, how, or why it happened.
SEQUENCE
The timing of the injury changes the interpretation.
Two records may end with the same information: âan injury occurred.â
That does not mean they describe similar events.
In one encounter, a person may sustain an abrasion after falling while attempting to flee. In another, an injury may occur during a prolonged physical struggle on the ground. In another, an officer may be injured by an assault before being able to establish control.
When these events are reduced to a single final variable, an important part of the dynamics disappears.
HOME OFFICE · ENGLAND AND WALES
National systems already record injuries on both sides of the encounter.
National use-of-force statistics for England and Wales separately record injuries sustained by officers and by people subjected to police use of force.
Between April 2023 and March 2024, 747,396 use-of-force reports were recorded. Each report represents one officer's use of force on one person and may include multiple tactics.
Within this dataset, officer injury was recorded in 3% of reports. Injury to the person subjected to force was recorded in 4%.
01 747,396
use-of-force reports recorded during 2023/24.
02 3%
recorded an officer injury.
03 4%
recorded an injury to the person subjected to force.
Among the 31,900 reports in which an injury to the person was recorded, 91% were classified as minor injuries and 2% as severe; in 7%, the injury level was not recorded.
Among the 24,295 reports recording officer injury, 82% were classified as minor injuries, 2% as severe, and 16% did not have an injury level recorded.
DATA QUALITY
Even the definition of the question can change what appears in the statistics.
In the publication covering April 2024 to March 2025, the Home Office changed the question used to record injuries to the person.
The new recording method made it possible to distinguish whether the injury occurred during the use of force, whether it occurred separately from the use of force, or whether that relationship was not recorded.
The Home Office itself presents these data as official statistics in development and highlights the methodological change.
This distinction is relevant because it demonstrates a basic problem in research on police encounters:
NATIONAL INSTITUTE OF JUSTICE
Resistance and physical control are associated with injury risk.
A multi-agency evaluation funded by the National Institute of Justice â NIJ examined factors associated with injuries to officers and civilians in encounters involving police use of force.
Researchers found an association between increasing levels of resistance and increased injury risk for both officers and people subjected to police intervention.
The use of physical force and hands-on control also appeared to be associated with a greater risk of injury.
The increased risk associated with resistance was particularly relevant for officers.
These findings help demonstrate why âforce was usedâ is too broad a category to explain an injury on its own.
1,174 ENCOUNTERS
Physical resistance appears again.
Another study analyzed 1,174 use-of-force encounters to identify factors potentially associated with injuries to the person and to the officers involved.
The person's physical resistance appeared among the factors with the strongest independent association with both injuries to the person and injuries to officers.
In the model presented by the researchers, physical resistance was associated with higher odds of injury to the person and also with higher odds of officer injury.
This does not make resistance an automatic explanation for every injury. The study identifies associations within a specific population, system, and time period.
ONE VARIABLE, MULTIPLE PROBLEMS
âInjuryâ is not a simple category.
Interpreting an injury requires separating different dimensions.
Who was injured, how severe the injury was, and when during the encounter it occurred are different questions.
01
Who?
The person being detained, an officer, or more than one participant may sustain injuries during the same encounter.
02
When?
Before physical contact, during resistance, during a fall, on the ground, during restraint, or at another point.
03
Severity
Abrasions and minor bruising cannot be treated analytically in the same way as fractures, deep lacerations, or hospitalization.
04
Mechanism
Impact with the ground, strike, fall, bodily contact, equipment, or an undetermined mechanism.
05
Visibility
The existence of a recording does not mean that the moment of injury is visible or can be determined reliably.
06
Source
Police records, medical care, subsequent accounts, and video may answer different questions about the same event.
ASSOCIATION â CAUSATION
A complex encounter produces variables that occur together.
This is one of the main methodological problems in studying injuries during police encounters.
Encounters involving more intense resistance may last longer, involve more officers, more attempts at control, contact with the ground, and greater use of force.
If an injury occurs more frequently in these encounters, this does not automatically establish that a single technique, position, or number of officers caused the outcome.
The same characteristics that make an encounter more difficult may simultaneously increase the likelihood of different interventions and injuries.
REAL-WORLD ENCOUNTERS
What must an analysis be able to distinguish?
The study of an encounter must go beyond the binary variable âinjury occurred / no injury occurred.â
01
Who sustained the injury?
02
Was the injury visible before physical contact?
03
Can the probable moment of injury be identified?
04
Did the injury occur during resistance, a fall, restraint, or at another point?
05
Did the person continue to resist after the observed moment?
06
Did more than one officer physically participate?
07
Was the encounter already on the ground?
08
Did the injury occur before, during, or after handcuffing?
09
Can the severity be determined from the available evidence?
10
When the evidence does not allow the mechanism to be determined, is this explicitly recorded as undetermined?
COMBATIVES RESEARCH · CS-001
The outcome must remain connected to the sequence.
CS-001 â COMBATIVES Physical Control Study
Observational Study of the Dynamics of Resistance and Physical Control in Police Encounters
In CS-001, the presence of an injury matters as one of the possible outcomes of an encounter, but its interpretation depends on the observable context.
The study seeks to preserve the relationship between resistance, the progression of physical contact, restraint, handcuffing, custody, and outcomes without turning observational associations into causal conclusions.
When the available evidence does not allow the timing or mechanism of an injury to be determined reliably, that uncertainty should not be filled by inference.
NEXT ARTICLE
Training a skill does not mean keeping it available.
Physical control techniques depend on learning, repetition, and the ability to perform them.
But there is one variable that is frequently overlooked: the time between training and the moment when that skill needs to be used.
The next article examines training, practice, skill deterioration, and performance retention.
SOURCES & REFERENCES
Injuries must be interpreted within the context in which they were recorded.
Home Office · England and Wales
Police use of force statistics, England and Wales: April 2023 to March 2024. Official statistics on tactics, context, outcomes, and injuries in use-of-force records.
Home Office · England and Wales
Police use of force statistics, England and Wales: April 2024 to March 2025. Official publication incorporating a methodological change in the recording of injuries to the person and distinguishing the relationship between the injury and the use of force.
Home Office · User Guide to Police Use of Force Statistics
Methodological guide for interpreting the categories, definitions, limitations, and recording procedures used in the national statistics.
Smith, Michael R.; Kaminski, Robert J.; Alpert, Geoffrey P.; Fridell, Lorie A.; MacDonald, John; Kubu, Bruce
Multi-Method Evaluation of Police Use of Force Outcomes. National Institute of Justice, 2009.
Alpert, Geoffrey P.; Smith, Michael R.; Kaminski, Robert J.; Fridell, Lorie A.; MacDonald, John; Kubu, Bruce
Police Use of Force, Tasers and Other Less-Lethal Weapons. National Institute of Justice, 2011.
MacDonald, John M.; Kaminski, Robert J.; Smith, Michael R.
Effect of Less-Lethal Weapons on Injuries in Police Use-of-Force Events. American Journal of Public Health, 2009.
Observational studies can identify associations, but they do not independently demonstrate that resistance, a particular technique, body position, number of officers, or another variable caused an injury. More complex encounters may simultaneously produce greater resistance, greater physical intervention, and greater injury risk.
The statistics cited belong to specific jurisdictions, time periods, definitions, and recording systems and should not be automatically transferred to the Brazilian context. Changes in definitions or data-collection procedures may also affect comparisons between periods.
External references are used for literature review and the conceptual development of CS-001. They do not constitute original data or findings from the study. The citation of researchers, institutions, and organizations is solely for documentary and research purposes and does not imply affiliation, certification, support, sponsorship, or institutional endorsement of COMBATIVESâą.
COMBATIVES RESEARCH · CS-001 · ARTICLE 06
The injury appears at the end of the record. The explanation may lie much earlier.
Physical encounters are sequences, not snapshots.
Resistance, falling, going to the ground, control, the participation of additional officers, and handcuffing can occur within seconds and produce different outcomes.
If the objective is to understand those outcomes, simply recording that someone ended the encounter injured is not enough.
When it happened.
What can be observed.
What remains undetermined.