There are two considerations that the law takes into account when defending a charge of assault to define whether or not it qualifies as a reasonable amount of force, and therefore self-defense.

  1. On reasonable grounds, the accused believed the amount of force used to defend him/herself or another person was necessary.
  2. The belief was reasonable.

Therefore, when in a situation of unprovoked assault you think might condone self-defense, you must consider very carefully what the circumstance is and what quantity of force is a reasonable minimum for that situation.

Elements to assess in these situations include:

  • Intent – How and what the person is saying, their body language. Could your own be seen as provoking?
  • Opportunity – Where are they? Does your environment provide sufficient exits or any obstacles.
  • Ability – Consider and compare both of your abilities: gender, size, fitness, weight, height
  • Method or weapons – Is the encounter likely to be purely body to body or will any type of weapon be involved? What type of resources do you both have at your disposal?
  • What are the options? – Is the person more likely to escape or attack? In either case will you be able to negotiate or escape, or will defence be required?

In any case, it is likely you will need to defend your actions in court, so it is crucial for all security officers to determine carefully what would be seen as reasonable force on all accounts.


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