PastPaperHero | Negligence - The standard of care

Learning Outcomes

This article explains the standard of care in negligence doctrine, including:

Defining the general negligence duty and articulating the objective reasonable person standard across varied fact patterns.
Distinguishing ordinary negligence cases from those triggering special standards for professionals, children, common carriers, and innkeepers.
Evaluating how physical disabilities, mental impairments, and intoxication interact with the reasonable person test on modern MBE questions.
Applying the child standard and the adult-activity exception when minors engage in inherently dangerous or adult-only conduct.
Assessing the impact of custom, trade practice, and professional guidelines as evidence of the applicable standard of care.
Using safety statutes to identify when negligence per se substitutes for the ordinary standard and when violations are merely evidence.
Conducting a structured breach analysis using the Hand formula, statutory violations, custom, and emergency circumstances.
Spotting common MBE traps, such as over-weighting mental characteristics or mislabeling heightened duties, and selecting the best answer choice.

MBE Syllabus

For the MBE, you are required to understand negligence standards of care with a focus on the following syllabus points:

The general reasonable person standard and its objective nature.
Special standards of care for professionals, children, common carriers, innkeepers, and others.
The effect of physical disability, intoxication, and mental characteristics on the standard.
The role of custom, statutes, and emergencies in setting or informing the standard of care.
How breach of duty is evaluated relative to the applicable standard, including negligence per se and related doctrines.

Test Your Knowledge

Attempt these questions before reading this article. If you find some difficult or cannot remember the answers, remember to look more closely at that area during your revision.

Which of the following best describes the general standard of care in negligence?
1. The standard of an average person in the community.
2. The standard of a reasonable person under the circumstances.
3. The standard of a person with the defendant's actual mental abilities.
4. The standard of a person with the plaintiff's physical characteristics.
A 10-year-old child causes injury while riding a bicycle. What standard of care applies?
1. The reasonable adult standard.
2. The reasonable child of similar age, intelligence, and experience.
3. Strict liability.
4. The professional standard.
In a medical malpractice case, which standard of care is used to judge the defendant doctor?
1. The reasonable person standard.
2. The standard of a reasonable doctor in the same or similar circumstances.
3. The standard of a reasonable patient.
4. Strict liability.

Introduction

Negligence law requires that individuals act with reasonable care to avoid causing harm to others. The "standard of care" defines the level of caution and judgment expected in a given situation. This article explains how the standard is set, when special standards apply, and how courts determine if a defendant has breached their duty.

Understanding the standard of care is critical on the MBE because many negligence questions do not turn on duty or causation, but on whether the defendant’s conduct fell below the applicable standard.

Key Term: Standard of Care
The level of caution and conduct required by law, measured against what a reasonable person (or relevant category of defendant) would do in similar circumstances.

The General Standard: The Reasonable Person

The default standard in negligence is that of a "reasonable person under the circumstances." This is an objective test. The law asks: Would a hypothetical reasonable person, in the defendant’s position, have acted differently?

Key Term: Reasonable Person Standard
The objective legal standard requiring individuals to act as a hypothetical ordinary, prudent person would act in similar circumstances.

Key Term: Objective Standard
A standard that does not vary with a defendant’s personal mental traits, but instead compares the defendant’s conduct to that of a hypothetical reasonable person.

Key features of the reasonable person standard:

It is objective: the defendant is judged against an external benchmark, not their own subjective judgment.
It assumes ordinary prudence and ordinary mental capacity.
It is context-sensitive: the circumstances (e.g., time of day, weather, obvious risks) inform what reasonable care requires.

Some refinements tested on the MBE:

Superior knowledge or skill: If a defendant actually has superior knowledge or skill (e.g., a highly experienced driver), the reasonable person standard incorporates that knowledge. They must use what they know.
Lack of experience is not a defense: Being a new driver, novice climber, or first-time homeowner does not lower the standard.

Physical and Mental Characteristics

Physical characteristics of the defendant are taken into account. For example, a blind person is judged as a reasonable blind person. However, mental characteristics (such as low intelligence or mental illness) are generally not considered—defendants are held to the standard of a person with average mental ability.

Key Term: Common Carrier Standard
The duty imposed on common carriers to exercise a very high degree of care toward passengers, traditionally described as “utmost care consistent with the practical operation of the business.”

Important points:

Physical disabilities: A defendant with a physical disability (e.g., blindness, mobility impairment) is compared to a reasonable person with that disability, under similar circumstances.
Mental disability: Most jurisdictions still hold mentally impaired defendants to the same reasonable person standard as those without such impairments. Mental illness or low intelligence does not lower the standard.
Intoxication: Voluntary intoxication does not reduce the standard of care. A voluntarily drunk person is held to the same standard as a sober reasonable person. Involuntary intoxication (e.g., drugged without consent) may be treated like a physical condition and considered in setting the standard.

These rules are frequently tested: if you see “schizophrenia,” “low IQ,” or “voluntary intoxication,” assume the defendant is still held to the ordinary reasonable person standard unless the fact pattern clearly indicates involuntary intoxication or a physical impairment.

Special Standards of Care

Certain defendants are held to a different standard. On the MBE, these special standards appear frequently and are tested with precision.

Professionals

Professionals (e.g., doctors, lawyers, accountants, architects) must act with the skill and knowledge normally possessed by members of their profession in good standing. The standard is measured by the profession's customary practices, not the average person.

Key Term: Professional Standard
The duty requiring professionals to exercise the care, skill, and knowledge commonly possessed by members of their profession in good standing under similar circumstances.

Key professional points:

The question is not whether the defendant acted as a reasonable layperson would, but as a reasonable professional with similar training and experience.
Custom is central: Professional malpractice is often framed as deviation from customary practice.
For physicians, many jurisdictions now apply a national standard for specialists and a “same or similar community” standard for general practitioners, but the MBE usually phrases it generically as “a reasonable physician under the circumstances.”

Children

Children are held to the standard of a reasonable child of similar age, intelligence, and experience. However, if a child engages in an adult activity (such as driving a car), the adult standard applies.

Key Term: Child Standard
The standard of care applied to minors, based on what a reasonable child of similar age, intelligence, and experience would do in similar circumstances.

Details likely to appear on the MBE:

The child standard is subjective-objective: the jury can consider this particular child’s age, intelligence, and experience.
Many jurisdictions treat very young children (often under age 5) as incapable of negligence as a matter of law, though the exact age threshold varies.
Adult activities: When a child undertakes a dangerous adult activity (e.g., operating a motor vehicle, power boat, snowmobile), the ordinary adult reasonable person standard applies.

Common Carriers and Innkeepers

Common carriers (e.g., bus companies, railroads, airlines) and innkeepers (e.g., hotels) have historically owed heightened duties to passengers and guests, because of the special dependence and vulnerability involved.

Common carriers and innkeepers (e.g., hotels) owe a higher duty of care to their passengers and guests. They must exercise utmost care consistent with the practical operation of their business.

Modern refinements you should know:

Common carriers: A majority of courts still describe their duty as “utmost care” or “very high degree of care” toward passengers.
Innkeepers: Many modern courts now hold innkeepers to ordinary reasonable care under the circumstances, rather than a heightened “utmost care” standard, but exams often describe them as owing a high duty of care.

On the MBE, focus less on the label (“utmost” vs “ordinary”) and more on whether the carrier/innkeeper took precautions a reasonably careful enterprise in that business would take to protect passengers or guests from foreseeable harm.

Automobile Drivers and Other Specific Roles

Some other roles have historically had special standards, but the MBE usually folds them into ordinary reasonable care:

Automobile drivers: Today, most jurisdictions impose an ordinary reasonable care standard to all drivers, including toward social guests. Old “guest statutes” (requiring gross negligence) may appear only in older questions or as background.
Bailments: The detailed “slight/ordinary/great care” distinctions are largely obsolete; modern courts usually apply a general reasonable care standard, adjusted for who benefits and who has control.

Emergencies

In emergencies not caused by the defendant, the standard is that of a reasonable person under the same emergency conditions.

Key Term: Emergency Doctrine
A rule that a person confronted with a sudden, unexpected emergency not of their own making is judged by how a reasonable person would act under the same emergency conditions.

Key exam points:

The emergency must be sudden and unforeseen, and not created by the defendant’s own negligence.
The emergency does not excuse unreasonable conduct; it just changes what counts as reasonable. For example, swerving abruptly to avoid a child darting into the street may be reasonable even if it would otherwise seem careless.

Custom and Statutes

Customary practices may be evidence of the standard of care but are not conclusive. Compliance with or deviation from custom is relevant but not determinative.

Key Term: Custom
The usual or accepted way of doing things in a trade, profession, or community; used as evidence of what reasonable care requires, but not automatically controlling.

Evidence of negligence: If most actors in a field take a particular safety precaution and the defendant does not, that deviation is strong evidence of breach.
Evidence of due care: If the defendant follows custom, that supports reasonableness, but the jury may still find negligence if the custom itself is unreasonable.

Statutes may set the standard of care if they are designed to protect a class of persons from a particular type of harm. Violation of such a statute may be negligence per se.

Key Term: Negligence Per Se
The doctrine treating violation of a safety statute as automatic breach of the standard of care if the statute protects the plaintiff's class from the type of harm suffered, and the violation is unexcused.

Typical negligence per se elements:

The statute clearly defines the required conduct.
The plaintiff is in the class of persons the statute intends to protect.
The harm is the type of harm the statute intends to prevent.
The defendant’s violation is a cause of the harm.
The violation is not excused (e.g., compliance impossible, or compliance would create greater danger).

Consequences:

If all elements are met, the statute replaces the ordinary reasonable person standard for breach: violation is conclusive (or at least very strong) evidence of breach.
If an element is missing (wrong class or harm type), the violation may still be some evidence of negligence, but not negligence per se.

MBE twist: Statutes can be used both against defendants (to establish negligence per se) and against plaintiffs (to establish contributory or comparative negligence per se when plaintiff violated a safety statute).

Exam Warning

On the MBE, do not apply the defendant’s actual mental ability or personal idiosyncrasies to the standard of care. The test is objective, except for physical disabilities.

Revision Tip

Remember: Statutory violations are not always negligence per se—check if the statute was meant to protect the plaintiff’s class from the type of harm suffered and consider possible excuses.

Breach of Duty

A defendant breaches the duty of care by failing to act as a reasonable person would under the circumstances. Courts may use the "Hand formula" (balancing the burden of precautions against the probability and severity of harm) or look to evidence of custom, statutory violations, or the facts of the case.

Key Term: Breach of Duty
The failure to meet the applicable standard of care—conduct that falls below what a reasonable person (or relevant special-standard actor) would do in similar circumstances.

Key Term: Hand Formula
An economic test for breach: a defendant is negligent if the burden of precaution (B) is less than the probability of harm (P) times the gravity of loss (L), i.e., if B < P × L.

Role division:

The court determines what duty and standard apply as a matter of law.
The jury normally decides whether the defendant’s conduct breached that standard, unless no reasonable jury could disagree.

Evidence relevant to breach:

Violation of a safety statute (negligence per se or evidence of negligence).
Deviation from or compliance with custom.
The Hand formula (when explicitly described).
Sometimes res ipsa loquitur (when the accident ordinarily does not occur absent negligence and is within the defendant’s control) is used to infer breach, though that doctrine is more commonly treated as a causation/inference tool.

Worked Example 1.1

A delivery driver is texting while driving and hits a pedestrian. The jurisdiction has a statute prohibiting texting while driving. Is the driver negligent?

Answer:
Yes. The driver failed to act as a reasonable person would and violated a safety statute designed to prevent this type of harm (injuries caused by distracted driving to road users). The pedestrian is within the protected class, and being hit by a texting driver is the type of harm the statute aims to prevent. Unless a valid excuse applies (unlikely here), this is negligence per se: breach is established as a matter of law.

Worked Example 1.2

A 12-year-old child injures another child while playing baseball. What standard applies?

Answer:
The child is held to the standard of a reasonable 12-year-old with similar intelligence and experience, not the adult standard. Ordinary risks of children’s games (e.g., a wild throw during normal play) may not be negligent at all under that child-standard, even if the same act would be negligent for an adult in a different context.

Worked Example 1.3

A surgeon performs a procedure in a way that most surgeons in the community would not. The patient is injured. What standard applies?

Answer:
The surgeon is judged by the professional standard—what a reasonable surgeon, with similar training and experience, would do in similar circumstances. Deviation from accepted medical practice is strong evidence of breach; if the surgeon used a technique outside customary practice without good reason, a jury may find professional negligence.

Worked Example 1.4

A bus company operates routes between major cities. To avoid a delay, the driver decides to let passengers off at an unlit spot about a half-mile from the designated, well-lit drop-off lot. While walking from this spot, a passenger is attacked and injured by an unknown assailant. Can the passenger recover from the bus company?

Answer:
Likely yes, if she can show the driver failed to meet the standard of care for a common carrier. Common carriers owe passengers a very high degree of care while they are passengers and during boarding and alighting. Dropping passengers in an unlit, less safe location to save time may fall below that heightened standard if a reasonable carrier would have foreseen an increased risk of crime and would have used the designated, safer lot.

Worked Example 1.5

The owner of a bed-and-breakfast allows upper-floor windows to open fully onto the beach below. There is no statute requiring locks, but all other bed-and-breakfasts in town use locks that limit the opening to four inches. A guest, after drinking heavily, leans out, falls, and is injured. In a jurisdiction that has abolished special innkeeper rules, has the owner breached the standard of care?

Answer:
The jury may find no breach as a matter of law. Custom (other inns using window locks) is evidence that a reasonable inn might install locks, but it is not conclusive. The owner can argue that no prior accidents occurred and the windows passed recent safety inspection. The absence of a statutory requirement and the fact that locks are not universal may lead a court to leave the issue to the jury rather than directing a verdict for the guest.

Worked Example 1.6

In a contributory negligence jurisdiction, a statute prohibits texting while driving. A plaintiff, stopped at a red light and texting, is rear-ended at high speed by a taxi whose driver is not texting. The plaintiff sues the taxi driver. The driver argues the plaintiff was negligent per se because he was texting. Is this defense likely to succeed?

Answer:
No. Even assuming the texting statute applies (it protects drivers and others on the road from crash-related injuries), the plaintiff’s violation must be a cause of the accident to bar recovery. Here, the plaintiff was stopped at a red light; his texting did not cause the taxi to rear-end him. Without causal connection, the plaintiff’s statutory violation cannot serve as contributory negligence that bars recovery.

Key Point Checklist

This article has covered the following key knowledge points:

The reasonable person standard is objective and applies in most negligence cases.
Physical disabilities are considered; mental disabilities are not, and voluntary intoxication does not lower the standard of care.
Defendants with superior knowledge or skill are expected to use it; novices are not excused by inexperience.
Professionals are judged by the professional standard—what reasonable members of that profession customarily do.
Children are judged by a child-standard (similar age, intelligence, and experience), unless engaged in adult activities, in which case the adult standard applies.
Common carriers owe a very high duty of care to passengers; innkeepers traditionally have a higher duty, but many courts now apply ordinary care.
In genuine emergencies not created by the defendant, the standard is that of a reasonable person in the same emergency.
Custom is relevant but not conclusive evidence of the standard of care; courts may reject unsafe customs.
Safety statutes can define the standard of care; violation can constitute negligence per se if the class-of-person and type-of-harm tests are met and no excuse applies.
Breach occurs when conduct falls below the required standard; courts and juries evaluate breach using custom, statutes, the Hand formula, and in some cases res ipsa loquitur.

Key Terms and Concepts

Standard of Care
Reasonable Person Standard
Objective Standard
Professional Standard
Child Standard
Common Carrier Standard
Emergency Doctrine
Custom
Negligence Per Se
Breach of Duty
Hand Formula

Negligence - The standard of care