The reasonable person test is a benchmark of behaviour for determining whether something is reasonable or not. The idea of a reasonable person is a made-up concept used to help apply the law consistently.
The reasonable person is a fictional person who exercises reasonable judgement and skill. Various areas of law, such as employment law, contract law, and torts, use the reasonable person test.
Using the test of the reasonable person assists with objectivity. Without being objective, standards of behaviour may differ too greatly as to what is considered ‘reasonable’.
Our commercial contract lawyers discuss ‘the reasonable person’ test and what it means in different scenarios.
Key takeaways
The reasonable person test is an objective legal standard. This standard is used to assess whether someone has fallen short of a standard of behaviour, for example whether someone has been negligent
The reasonable person test asks whether a hypothetical, sensible person would have acted the same way in similar circumstances
The test ensures consistency and fairness by removing personal bias or subjectivity
Personal characteristics may modify the standard in specific cases, such as disability or age
States and Territories across Australia have legislation which reflects the reasonable person test
Who is a 'reasonable person'?
The reasonable person is a hypothetical individual used by Australian courts to assess whether a defendant has breached their duty of care in negligence cases. This standard asks whether an ordinary person, exercising reasonable care and prudence in similar circumstances, would have acted as the person did.
The reasonable person is not the average person, nor is they exceptionally cautious or skilled. Rather, they represent a standard of ordinary care. For example:
- if a driver runs a red light and causes an accident, the court considers whether a reasonable person would have acted differently. If so, the driver may be found liable.
- however, if an unforeseeable event—such as sudden brake failure—occurs, even a prudent driver may not have avoided the harm.
The reasonable person test is applied when assessing whether a person has breached their duty of care, such as a shopkeeper’s obligation to keep premises safe or a factory’s duty to manage hazardous waste responsibly.
Why is the test used?
The reasonable person test is said to be purely objective. In all Australian states (other than South Australia). The standard of care is that of a reasonable person in that person’s position, to be determined on the basis of:
- what the person knew or
- ought to have known at the time
The test operates fundamentally as a legal fiction that enables courts to establish consistent standards of behaviour across society. The reasonable person is said to provide a benchmark against which conduct can be measured objectively rather than subjectively.
It is objective because the individual’s belief or personal circumstances are (to some extent) irrelevant. What matters is what an ordinary, reasonable person would have done in similar circumstances.
How is the reasonable person test used?
Statutory use of the reasonable person
Most Australian states have civil liability statutes that require the same reasonable person standard for both negligence and contributory negligence. This is known as the equivalence theory.
Jurisdiction
Standard Applied
Key Statute/Provision
New South Wales
Reasonable person in that person’s position
Civil Liability Act 2002 (NSW) s 5B
Victoria
Reasonable person in that person’s position
Wrongs Act 1958 (Vic)
Queensland
Reasonable person in that person’s position
Civil Liability Act 2003 (Qld)
South Australia
Reasonable care and skill (unique approach)
Civil Liability Act 1936 (SA) ss 3, 46
Personal characteristics and standard of reasonableness
While the reasonable person test is fundamentally objective, courts may adjust it in certain situations:
- Physical or intellectual disability: The standard may be modified to account for the person’s limitations (e.g., a visually impaired person)
- Children: The “reasonable child” standard is applied, considering age and maturity
- Knowledge or awareness: What the person knew or ought to have known at the time is relevant
Interpretation by the courts
Courts use the test to assess both defendants (for liability) and plaintiffs (for contributory negligence). In other words, did the individual show the same level of care as an ordinary person would in similar circumstances?
How can the reasonable person test be used in business and the workplace?
Human error is a fact of life. It’s why many businesses that provide services or professional advice hold professional indemnity insurance. Professional indemnity insurance covers claims that a person failed to act with reasonable skill, care and diligence.
Standard of care of engineers
Engineers are skilled professionals and often engaged under professional engineering contracts. In the context of the reasonable person, engineers are held to the standard of a reasonable person possessing the same level of skill, training and experience in their profession. An engineer’s conduct is benchmarked against a competent engineer, which means that they must:
- foresee risks that a competent engineer in their position would anticipate
- take steps to prevent those risks
- act with competence, rather than perfection
An employer's duty of care
Employer’s need to act with reasonable care, particularly when it comes to ensuring the safety of its employees. In assessing whether an employer is negligent, Courts will assess what a reasonable employer would do in similar circumstances. This may be in the context of:
- providing a safe working environment
- supplying proper tools, equipment and training
- taking steps to prevent psychosocial injury, bullying and harassment
Case Examples
Vaughn v Menlove
The reasonable person test was first discussed in the old English case of Vaughn v Menlove (1837). In this case, the defendant stacked hay too close to a neighbour’s property, despite repeated warnings that it posed a fire risk. Eventually, the hay ignited, destroying barns, stables, and cottages.
The court held that the defendant failed to act as a reasonable person would have under the circumstances. The Court rejected his argument that he had acted to the best of his personal judgement. Negligence is assessed objectively, not based on individual intelligence or intent.
This case set a lasting precedent. Individuals are expected to meet the standard of ordinary prudence and caution, regardless of personal limitations.
McQuire v Western Morning News
In McQuire v Western Morning News, the court reinforced the objective nature of the reasonable person test. This case referenced the “passenger on the Clapham omnibus” – a symbolic, everyday person from a working-class London district.
The court emphasised that the standard does not rely on personal opinions or self-assessments, even if witnesses claim they would have acted the same. The focus remains on what a reasonable, average person would do in the same circumstances – not on subjective beliefs.
Frequently Asked Questions
How do I determine the standard of a reasonable person in Australia?
The relevant question is “What would a reasonable person have done (or not done) in the same circumstances to avoid foreseeable risk of harm?”. In answering this question, you need to consider:
- the context, for example whether the situation involves children or professionals
- whether the risk was foreseeable
- the likelihood and seriousness of the potential for harm
- the burden of taking precautions
- the social utility of the activity (for instance, greater leeway may be applied to emergency services)
How does the legal test of the reasonable person apply in negligence cases in Australian courts?
In Australia, negligence cases use the reasonable person standard. This standard helps determine if a defendant’s actions were not as careful as they should have been.
It applies to situations similar to theirs. This means considering how an average person would act in a similar situation. It also involves determining if the defendant breached the duty of care to the person that suffered harm.
Learn more about gross negligence in our article.
Can the standard vary depending on the circumstances in Australian law?
Yes, the standard of the reasonable person can vary depending on the circumstances in Australian law. Courts consider factors such as the industry or profession. They also consider the expected level of expertise and any relevant laws or standards.
Additionally, we may adjust the standard to accommodate the characteristics and capabilities of individuals, such as children or people with disabilities.
