Difference Between a Breach of Duty and Causation: Key Legal Concepts Explained

During medical negligence cases, it is common for individuals to encounter legal terms such as “breach of duty of care” and “causation.” A clear understanding of these terms is crucial for both the patient and healthcare professional. Breach of duty indicates that the medical professional has failed to provide an acceptable level of care, while causation refers to the direct link between this breach and the harm suffered by the patient.

Proving causation is a critical aspect of medical negligence claims. It establishes if the healthcare professional’s actions have directly or indirectly led to the patient’s injury or loss. To ensure a successful claim, it is important to assess whether their actions or inactions have breached the duty of care and whether the resulting harm can be legally attributed to this breach.

Key Takeaways

  • A breach of duty of care refers to substandard care provided by a medical professional
  • Causation indicates the direct connection between the healthcare provider’s breach and the patient’s harm
  • Establishing causation is vital in medical negligence cases, as it helps determine if the claim is valid

What Constitutes a Breach of Duty of Care?

breach of duty of care occurs when a medical professional fails to deliver the expected standard of care to their patient. In cases of medical negligence, proving a breach is one of the two primary legal principles required, with the other being causation. When a doctor, consultant, hospital, or staff member provides treatment that falls below the normal level of care, it may give rise to a breach of duty of care, deeming the treatment as negligent.

After establishing negligence, one must determine if the negligent treatment led to causation. This is vital in understanding the consequences of the breach and deciding on the legal outcome.

Difference Between Breach of Duty and Causation in Medical Negligence Cases

Breach of duty, also known as negligence, occurs when a medical professional’s treatment falls below the expected standard of care for their patients. This could involve a doctor, hospital, or care provider failing to provide adequate care.

On the other hand, causation refers to the consequences resulting from the breach of duty. This could manifest as a delayed recovery, additional injuries, or even the patient’s death due to improper treatment. In essence, causation is the relationship between the breach of duty and the adverse outcomes experienced by the patient.

Two types of causation are often considered in medical negligence cases: legal causation and factual causation. Legal causation relies on the ‘but for’ test, meaning that if not for the negligence, would the injury still have occurred? Factual causation, conversely, requires proof that the defendant’s failure directly led to the injury.

It’s important to keep in mind that establishing a breach of duty alone is insufficient; one must also demonstrate causation between the breach and the subsequent harm to successfully prove medical negligence.

How Causation Influences Medical Negligence

Causation’s role in medical negligence cases is to establish a connection between the breach of duty and the harm experienced by the patient. This involves examining whether the patient’s pain, further injury, or death could have been averted if appropriate care had been provided.

Owing to the complex nature of medical treatments and multiple factors that can influence their outcomes, determining causation with absolute certainty can be challenging. Therefore, courts assess the merits of a case based on the “balance of probabilities,” weighing the strength of evidence presented by both the plaintiff (patient) and defendants (care providers).

To claim compensation in medical negligence cases, it is crucial to prove that the negligent behaviour of the care provider was responsible for the patient’s harm. Establishing causation ultimately demonstrates that the failure in providing correct treatment led to the patient’s suffering, making it a vital component in securing appropriate compensation for the victim.

How to Establish Causation in Medical Negligence Cases

Proving Breach of Duty and Causation: The “But-For Test”

In medical negligence cases, it’s crucial to establish causation, which means proving that the negligence of the medical professional directly led to the patient’s injury. One common approach to determine causation is the “but-for test”.

The “but-for test” can be summarised as: “If not for the negligent action of the medical practitioner, the injury would not have occurred.” This test is applied to analyse whether a breach of duty has a causal link to the injury or worsened health condition of the patient.

However, in some medical negligence cases, a breach of duty may occur without having a material impact on the patient’s recovery. It has been found that in approximately 30% of such cases, expert reports may identify a breach of duty, but the breach does not lead to an injury or affect the recovery of the patient. In these cases, there is no causal link between the action and the injury, and the “but-for test” won’t be satisfied.

To prove causation, the following aspects should be considered:

  • Defendant: Identify the medical professional(s) responsible for the alleged breach of duty.
  • Prove: Present substantial evidence that supports the claim of medical negligence.
  • Evidence: Gather expert testimonies and relevant medical records that showcase the defendant’s failure in their duty of care.
  • Patient: Demonstrate how the negligence impacted the patient’s health condition or recovery process.
  • But-for: Apply the “but-for test” to ascertain whether the injury would have happened without the medical practitioner’s negligence.
  • Balance of probabilities: Weigh the likelihood of the injury occurring due to the defendant’s negligence.
  • Burden of proof: Keep in mind that the responsibility for proving negligence lies with the patient.
  • Causal link: Dissect the chain of events leading to the injury to highlight the connection between the breach of duty and the patient’s injury.
  • Material contribution: Evaluate the significance of the medical practitioner’s negligence in the overall outcome for the patient.

Using these principles, clients can assess the strength of their case and navigate the legal process of a medical negligence claim more effectively. It is essential to be guided by experienced legal professionals who have a thorough understanding of these complex aspects and can provide clear, knowledgeable advice throughout the process.

Case Study: Evaluating Breach of Duty, Negligence and Causation


An 18-year-old young man sought treatment at a Dublin hospital after sustaining a fracture to his right index finger during a football match. Initially, an x-ray was performed, but the fracture was not identified. His fingers were strapped, and he was informed that healing would occur within two weeks without a follow-up appointment.

Over the next eighteen months, the young man continued to experience pain, swelling, and difficulties writing, impacting his academic performance. After consulting with his GP, he underwent an additional x-ray, revealing a prior fracture that resulted from the football injury.

Identifying the Absence of Causation:

A UK expert was consulted to review the patient’s medical records. They confirmed that the initial hospital visit failed to recognise and record the fracture, indicating that the emergency department and reporting radiologist fell below a reasonable standard of care. Additionally, the lack of follow-up advice in case of persistent symptoms was considered inadequate.

Despite these shortcomings, it was determined that causation could not be established. The expert concluded that even if the fracture had been correctly diagnosed during the initial visit, the treatment – strapping the finger – would have been the same. Furthermore, the expert opined that the persisting symptoms, such as pain, swelling, and weakness, would not have been prevented or alleviated through follow-up appointments.

In cases like this, it is crucial to seek legal advice from specialist solicitors with expertise in medical negligence claims to properly navigate the complexities of establishing causation and breach of duty.

Frequently Asked Questions

What is a breach of duty in negligence law?

A breach of duty occurs when a person fails to meet the required standard of care in a specific situation. In negligence law, this typically involves a professional providing a level of care that falls below the standard expected of a reasonably competent person in their field. For example, a medical professional not providing an acceptable level of care to their patient would be considered a breach of duty.

How do you establish causation in a negligence case?

Causation is established in a negligence case by proving that the defendant’s breach of duty directly resulted in the claimant’s harm or loss. This is commonly demonstrated using the “but for” test, which asks whether the harm would have occurred if it were not for the defendant’s actions. To satisfy the causation requirement, the claimant must show that, without the breach of duty, the harm would not have occurred.

What is the difference between direct and proximate causes in tort law?

  • Direct cause: A direct cause is the immediate and actual cause of an event leading to a harmful outcome. It is the action or omission by the defendant that directly results in the claimant’s harm.
  • Proximate cause: A proximate cause is a cause that is legally sufficient to establish liability, even if it is not the immediate or direct cause of the harm. It typically involves a sequence of events that can reasonably be foreseen to lead to the harmful outcome.

How does the “but for” test relate to establishing causation in negligence cases?

The “but for” test is used in negligence cases to establish a factual link between the defendant’s breach of duty and the claimant’s harm. The test asks, “but for the defendant’s actions, would the harm have occurred?” If the answer is no, then the breach of duty is deemed to have caused the harm, fulfilling the causation requirement in a negligence case.

Can you clarify the role of foreseeability in determining a breach of duty?

Foreseeability plays a crucial role in determining whether a defendant owed a duty of care to the claimant, and whether their actions breached that duty. A breach of duty is deemed to have occurred if the defendant’s actions were reasonably foreseeable to cause harm and the defendant failed to take reasonable steps to prevent that harm.

What happens if a link between breach of duty and causation is not established in a negligence claim?

If a claimant is unable to establish a link between the breach of duty and causation, their negligence claim will likely fail. Both elements – breach of duty and causation – must be proven for a claimant to successfully pursue a negligence case. Without proving causation, the claimant cannot demonstrate that the defendant’s actions were responsible for their harm or loss.

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