The Reasonable Person

The Evolution of the Reasonable Person Standard

In law, the term “reasonable person” is used widely. Historically, the term “reasonable man” was commonly employed. However, with the adoption of the Constitution of the Republic of South Africa, 1996 (“the Constitution”), which stresses gender equality, the term “reasonable man” is increasingly considered inappropriate due to its sexist connotations. Therefore, to maintain gender neutrality, the appropriate term is “reasonable person”. But who or what is the reasonable person? And how do they fit into the law?

The standard of the reasonable person, or its equivalent, is widely employed in various jurisdictions to assess fault in cases of negligence. In essence, the concept of the reasonable person is a fictional construct created by law to embody the objective standard of conduct used to determine negligence. It represents the qualities that the community expects from its members in daily interactions.

In legal literature, the reasonable person is often equated with the bonus paterfamilias or diligens paterfamilias. The former translates to “the good father of the family”, and the latter to “the diligent father of the family”. These terms originated in Roman law, where the conduct of this idealised male, typically married, was the measure of what was deemed reasonable. Today, however, they serve merely as shorthand for the “reasonable person”.

The reasonable person refers to an ordinary, average individual of ordinary intelligence and knowledge.¹ This person is neither exceptionally gifted nor recklessly inclined. Rather, their characteristics lie between these extremes.² Thus, the reasonable person is not one who avoids every foreseeable danger but is capable of taking a reasonable risk in appropriate circumstances.³

It is essential to recognise that the reasonable person standard must adapt to evolving societal conditions. For instance, in light of rising crime rates that threaten lives and property, it would be unreasonable to assume that the reasonable person would be devoid of fear or nervousness in dangerous situations. Conversely, advancements in technology and access to education may necessitate a stricter application of the reasonable person test, particularly in assessing the care expected in specific contexts.

The reasonable person test is grounded in objectivity. Personal characteristics such as gender, race, emotional state, education, or superstition are irrelevant.⁴ However, when expertise is required, negligence is assessed against the standard of a reasonable person possessing the relevant knowledge or skill.⁵ The more personal characteristics are taken into account, the more subjective the test becomes.

In negligence cases, courts focus on external factors (e.g., whether a person drove in heavy rain) but exclude personal characteristics (e.g., lack of experience or impaired hearing). If, for example, an individual’s reckless driving was due to unexpected brake failure, the court would assess how a reasonable person would have acted in that situation.⁶ However, if the driving was due to sleepiness, as in R v Shevill,⁷ the inquiry would centre on the reasonable person’s response to drowsiness behind the wheel, rather than the individual’s own physical state.

The reasonable person is not an infallible being but a human subject to the limitations of human nature. In a crisis, such a person may err in judgment.⁸ While the reasonable person is presumed to possess a basic level of knowledge and mental capacity to appreciate inherent dangers (e.g., the risks associated with motor vehicles, explosives, or electricity), the law does not account for a wrongdoer’s personal deficiencies, such as illiteracy or mental instability. Everyone is expected to conform to the objective standard.⁹ Nevertheless, there is a consensus that the knowledge of the wrongdoer is relevant when constructing the reasonable person.¹⁰

Notably, the law does not consider the physical characteristics of the wrongdoer, implying that all individuals, regardless of sex, must adhere to the same standard. However, as in Anglo-American law, physical disabilities may be taken into account when assessing negligence. For example, a blind person or someone with a severe visual impairment may still be held negligent if they engage in activities that a reasonable person in their circumstances would consider unsafe, such as driving a vehicle.

The expertise of the wrongdoer also influences the application of the reasonable person test. In cases requiring specialised knowledge, such as those involving engineers, surgeons, or police officers, the test shifts to that of the “reasonable expert”. This expert standard does not demand the highest level of proficiency but rather the general or average level of expertise within the relevant profession. In Van Wyk v Lewis,¹¹ the court considered the “general level of skill and diligence” exercised by practitioners within a profession, recognising that a general practitioner is not expected to possess the same level of expertise as a specialist.

Similarly, in Durr v ABSA Bank Ltd,¹² the Supreme Court of Appeal followed the Van Wyk v Lewis approach, emphasising that while the views of the relevant profession are influential, the court ultimately determines the reasonableness of conduct. In this case, the court concluded that the standard of care for an investment broker was not that of an average, modestly accomplished broker, but rather that of a regional manager of a broking division, who was expected to possess superior investment skills.

Written by Theo Tembo