Police officers may use force in specific situations as defined by legislation however just because an officer can use force, does not mean they should. What makes force justifiable can be placed into the acronym PLAN:
P - Proportionate - all uses of force must be proportionate to the threat presented;
L - Legal - all uses of force must be legal and backed up by the legislation shown below;
A - Accountable - All officers should be accountable if they use force;
N - Necessary - A use of force must be necessary for the circumstances.
There are 3 main pieces of legislation that govern the use of force by a police officer:
Common-Law - common law relates to self-defense and allows an officer to use force to protect themselves, another, or personal property.
Section 3 Criminal Law Act 1967 - An officer may use force to prevent crime or arrest a suspect unlawfully at large.
Section 117 PACE 1984 - A constable may use reasonable force when exercising any powers within the PACE act.
The following constitutes a use of force starting with the lowest and moving up to the most severe:
Presence
Voice
Handcuffs
Physical Contact such as grabbing/escorting
Striking with fists*
Use of Baton/ PARVA
Taser - Red Dot
Taser - discharge
Firearms - Challenge
Firearms - Discharge
*Striking with fists is only to be done in self-defense.
Officers should where possible use the ask, tell, make, method where possible before using force:
Ask - As a suspect to do something
Tell - Tell a suspect to do something and inform them of the consequences if they do not
Make - Use force to make a suspect comply.
As a Police officer, you should where possible attempt to de-escalate a situation and there are multiple ways this can be achieved:
Use of Trained negotiators
Listening to a suspect