Negligence: What It Is And How To Prove It
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Most personal injury cases proceed on a theory of negligence, a fundamental principle in tort law. Even product liability cases, which have the additional option of proceeding on strict liability, often involve negligence claims. Automobile accidents, slip and falls, dog bites, and numerous other personal injury cases rely on proving negligence to establish liability.
So, what is negligence, and how can you prove it?
What Is Negligence?
Negligence is legally defined as the failure to exercise reasonable care that a prudent person would use under similar circumstances. Courts evaluate negligence by examining whether a person’s actions—or lack of action—created a foreseeable risk of harm.
To prove negligence, a plaintiff must establish the following five elements:
- Duty of Care – The defendant owed a legal duty to the plaintiff.
- Breach of Duty – The defendant failed to meet the required standard of care.
- Harm/Injury – The plaintiff suffered actual harm (physical, financial, or emotional damage).
- Proximate Cause – The harm must have been a foreseeable result of the defendant’s actions.
- Cause-in-Fact (But-For Cause) – The harm would not have occurred but for the defendant’s conduct.
Let’s consider some examples:
Most adults are licensed and experienced operators of motor vehicles. So, most jurors have the experience to evaluate whether a defendant driver who hit another vehicle, resulting in injury, exercised due care. Motor vehicle cases are generally submitted to a jury on one or more of the following theories of recovery:
- Exceeding the speed limit;
- Failure to stop at a light or sign;
- Refusal/failure to yield the right of way;
- Failure to keep a careful lookout for vehicles and pedestrians;
- Impaired driving;
- Driving at a speed that was excessive given the conditions (e.g., rain, snow or ice).
In June 2024, a tragic incident occurred in Savannah, Missouri, where K-9 Officer Horus died from heat exposure after being left in a police vehicle by his handler, Lieutenant Daniel R. Zeigler. The vehicle’s heat protection system had been manually deactivated. Zeigler was subsequently charged with misdemeanor animal abuse. This case underscores the severe consequences of impaired judgment and negligence.
There are others, but the above list covers most potential theories for submitting negligence in a motor vehicle collision. Sometimes, an act of negligence is also covered by a law, such as exceeding a posted speed limit. When there is an applicable law, the case may progress on what is known as “negligence per se”. There is much less argument that someone was not negligent if the mere act was in violation of a law.
In motor vehicle collisions alone, negligence in Missouri requires an operator of a vehicle to adhere to the “highest degree of care.” This is usually defined as the failure to act a a “very careful” driver.
Legal Duty of Care
In many cases, the duty of care is based on a reasonable person standard—meaning the law expects people to act with the level of caution and responsibility that an ordinarily careful individual would in the same situation.
Courts consider several factors when determining whether a duty of care existed, such as:
- Creation of risk: Did the defendant’s actions contribute to the plaintiff’s harm?
- Voluntary undertaking: Did the defendant assume responsibility to protect the plaintiff?
- Foreseeability: Should the defendant have foreseen the risk?
- Special relationships: Certain relationships impose automatic duties of care (e.g., doctor-patient, business-customer, property owner-tenant).
Example: If a business owner fails to clean up a spill in a grocery store aisle, they may be liable for injuries caused by a customer slipping and falling. Their duty of care requires them to keep the premises safe.
Breach of Duty of Care
A breach occurs when a person fails to act with reasonable care, meaning they either:
- Acted in a way that created unnecessary risk, or
- Failed to take action when duty required it.
Some courts apply the Hand Formula (created by Judge Learned Hand in United States v. Carroll Towing) to assess whether the duty of care was breached:
B < PL = Negligence
Where:
- B = Burden of taking precautions
- P = Probability of loss
- L = Severity of loss
If the burden of taking precautions is less than the probability and severity of potential harm, failure to take precautions constitutes negligence.
Harm to the Plaintiff
To claim negligence, the plaintiff must show actual harm. Courts typically recognize:
- Physical injuries (e.g., broken bones, burns, concussions)
- Property damage (e.g., car accidents, home destruction)
- Emotional distress (varies by jurisdiction)
Example: A driver running a red light and causing a car crash would be responsible for injuries suffered by the other driver.
Proximate Cause (Legal Cause)
Proximate cause limits liability by assessing whether the defendant’s actions directly led to the injury. The standard test is foreseeability—if the injury was a reasonably predictable result of the defendant’s conduct, they are legally responsible.
Example: If a construction worker fails to secure scaffolding, causing tools to fall and hit a pedestrian, their negligence is the proximate cause of the injury.
However, if an unrelated event or third-party action intervenes, it may break the chain of causation, reducing the defendant’s liability.
Cause-in-Fact (“But For” Test)
A defendant’s negligence must be the actual cause of the plaintiff’s harm. Courts use the “but for” test:
- Would the injury still have occurred but for the defendant’s actions?
If the answer is no, the defendant’s negligence is considered the cause-in-fact.
Negligence In Sexual Abuse Cases
For example:
Consider a boarding school setting where multiple reports of inappropriate behavior by a staff member surface. If administrators dismiss these reports or do not take action to investigate, they not only violate their duty of care but also contribute to an environment where abuse can flourish. This negligence not only affects the immediate victims but can also lead to long-lasting psychological trauma, eroding trust in systems meant to provide safety and support.
Ultimately, recognizing and addressing negligence in cases of sexual abuse is crucial for fostering accountability and ensuring that survivors receive the justice and healing they deserve. It is a call to action for all of us to advocate for stronger protections and a culture of vigilance against such violations.
Proving Negligence In A Personal Injury Case
1. Motor Vehicle Accidents
Most negligence cases involve motor vehicle accidents. Common driver errors leading to liability include:
- Speeding
- Running a red light
- Distracted driving
- Drunk driving
- Failure to yield
Negligence in Missouri motor vehicle cases follows a higher standard—drivers must exercise the highest degree of care.
Example: In June 2024, a tragic incident occurred in Savannah, Missouri, where K-9 Officer Horus died from heat exposure in a police vehicle. His handler, Lieutenant Daniel R. Zeigler, had manually disabled the vehicle’s heat protection system. Zeigler was later charged with misdemeanor animal abuse. This case highlights criminal negligence, where reckless disregard for risk results in serious harm.
2. Premises Liability (Slip and Falls)
Property owners have a duty to maintain safe premises. Failing to remove hazards like wet floors, uneven surfaces, or poor lighting can establish negligence.
Example: If a store fails to remove ice from its entrance, leading to a customer’s injury, the store may be held liable.
3. Medical Malpractice
Medical negligence occurs when a healthcare provider breaches the standard of care, resulting in injury. Expert witnesses are often required to explain what a competent professional would have done differently.
4. Negligence in Sexual Abuse Cases
Institutions that fail to protect individuals from abuse can be held negligent. If a school, church, or employer ignores warning signs of abuse and fails to act, they may be legally responsible.
Example: If a boarding school repeatedly ignores complaints about an abusive staff member and a student is harmed, the school may be liable for negligence.
Let’s consider a different scenario. Imagine a building contractor hired to construct a staircase fails to comply with local building codes, resulting in an unsafe structure. A visitor using the staircase falls and sustains severe injuries. Expert testimony may be required to show how the staircase design or construction violated safety standards and how that breach caused the injury.
In this case, the contractor’s failure to follow established safety guidelines is the legal equivalent of the motorist who fails to stop at a stop sign. The only difference lies in how negligence is proven.
An expert in construction safety or structural engineering would likely be called to testify. This expert would explain the applicable building codes, identify the specific violations, and demonstrate how those violations directly led to the plaintiff’s injury. At the end of the case, the jury would determine whether the contractor was negligent, aided by the expert’s analysis to guide their decision.