LAWS5024 Chap.3 Defences to Trespass
Defences to Trespass
Defences to trespass are not a general appeal to reasonableness. Each defence has a trigger, purpose and boundary. This chapter compares self-defence, defence of others or property, necessity, consent and contributory negligence. It teaches students to establish the prima facie tort first, then state the precise legal effect of the defence and test whether the defendant's response stayed within its scope.
What this chapter covers
- 01
Self-defence and protective force
- 02
Defence of others and property
- 03
Necessity and imminent danger
- 04
Medical necessity
- 05
Express and implied consent
- 06
Contributory negligence as partial defence
Worked example · free
Emergency treatment after refusal
- +1Identify battery through injection and restraint before turning to justification.
- +2Assess whether the earlier refusal was valid, applicable and continuing in the later emergency.
- +3Test necessity through incapacity, imminent danger, therapeutic purpose and available alternatives.
- +2Ask whether the force and duration of restraint exceeded what treatment required.
Key terms
- Self-defence
- A justification for necessary and proportionate force used to protect against threatened harm.
- Necessity
- A narrow defence permitting interference to respond to real and imminent danger in appropriate circumstances.
- Consent
- Permission to conduct within an agreed express or implied scope.
- Proportionality
- The relationship between the threatened harm and the force or interference used in response.
- Partial defence
- A defence that reduces recovery rather than defeating liability entirely.
Defences to Trespass FAQ
Is reasonable conduct automatically self-defence?
No. Identify the threatened harm, the need to act and the proportionality of the response under the applicable common-law or statutory rule. A conclusion that conduct seemed reasonable does not establish the distinct requirements of self-defence.
When can necessity justify medical treatment?
Necessity can apply where a patient lacks capacity, faces a real and imminent danger and treatment is directed to that emergency without a less intrusive effective alternative. A valid and applicable refusal requires separate attention and may prevent reliance on necessity.
Does consent cover every act during sport?
Participation may imply consent to contacts inherent in the sport, but not necessarily deliberate violence outside its accepted incidents. Define the activity and scope of permission, then explain why the challenged act falls inside or outside that boundary.
What makes defensive force proportionate?
Compare the threatened harm, urgency and available alternatives with the force actually used. Property protection and personal protection may justify different responses. Proportionality is not a free-standing impression; connect it to what the defendant reasonably confronted at the time.
Can consent be withdrawn after it is given?
Consent operates within its current scope and can be limited or withdrawn in appropriate circumstances. Identify when withdrawal was communicated and whether the defendant had a fair opportunity to respond. Conduct after that point needs an independent justification.
Why is contributory negligence treated separately?
It can reduce damages for certain unintended consequences or negligent trespass, but it does not operate like consent or self-defence. State the statutory or common-law basis and its partial effect rather than using claimant carelessness to erase deliberate interference.
How should alternative defences be written?
Analyse each defence under its own trigger and boundary. The defendant may argue consent and, alternatively, necessity, but a weak consent case does not prove an emergency. Conclude separately so the reader can see which facts support each route.
Why does chronology matter in an emergency defence?
Necessity depends on the circumstances when action was taken, so identify when danger arose, what the defendant knew and which alternatives remained feasible. Earlier consent or refusal may have a different effect after capacity or urgency changes, but the later emergency does not erase the earlier event. Analyse every use of force separately for necessity and proportionality.
A timed sequence also exposes avoidable delay and shows whether the defendant created the predicament relied upon as justification.
Exam move
Prepare a defence matrix with columns for trigger, defendant's factual burden, scope, legal effect and common counterargument. Apply it only after completing the claimant's prima facie cause of action. For self-defence, practise separating perceived threat, necessity and proportionality. For necessity, identify the imminent danger and less intrusive alternatives.
For consent, write the precise conduct authorised and test withdrawal or excess. Always state whether the defence is complete or partial. That final classification prevents contributory negligence from being treated like consent or self-defence.
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