Back to Blog

Understanding Duty of Care in Medical Malpractice Cases in Ontario

Reading Time: 3 minutes

The concept of duty of care is fundamental to maintaining patient safety and trust. Healthcare providers have a legal obligation to ensure their patients receive competent care.

This blog explores the meaning of duty of care in the context of medical malpractice in Ontario, how breaches can occur, and the implications for both patients and healthcare providers following a breach of care.

What is Duty of Care?

Duty of care refers to the obligation of medical professionals to provide care to their patients at the standard expected of reasonably competent practitioners in their field. This duty encompasses a wide range of medical practices, including diagnosis, treatment, management, and follow-up care.

Establishing Duty of Care in Ontario

For a medical malpractice claim to be successful in Ontario, the plaintiff must first establish that a duty of care existed. The Plaintiff usually establishes a duty of care by demonstrating they had a professional relationship with a healthcare provider such as their physician, psychiatrist, counsellor, or other medical professional.

Breaches of Duty of Care

A breach of duty occurs when a healthcare provider fails to meet the standard of care expected of him or her during the course of their patient’s care. Examples of breaches include:

  • Negligence in Diagnosis: Misdiagnosing a condition or failing to diagnose a condition that a competent doctor would have identified.
  • Surgical Errors: Mistakes made during surgery that are not consistent with the level of care expected from a competent surgeon.
  • Inadequate Treatment: Providing treatment that deviates from accepted norms, which may involve administering the wrong medication, administering the incorrect dosage of medication, and/or failing to properly monitor a patient for side effects to the patient’s medication.
  • Poor Patient Management: Failing to monitor a patient’s condition or respond to changes in treatment adequately.

Legal Implications of a Breach in Ontario

When a duty of care is breached, and that breach causes the patient to suffer harm, the groundwork is laid for a medical malpractice claim in Ontario. The affected patient may be entitled to compensation for damages such as:

  • Medical Expenses: Costs for additional treatment needed due to the malpractice.
  • Lost Wages: Compensation for time off work and loss of earning capacity.
  • Pain and Suffering: Non-economic damages for the physical and emotional distress caused by the injury.

Proving a Breach of Duty in Ontario

Proving that a healthcare provider breached their duty of care involves showing that their actions deviated from what a reasonably skilled medical professional would have done under similar circumstances. This typically requires:

  1. Expert Testimony: Other medical professionals may need to testify about what the standard of care is and how the defendant failed to meet it.
  2. Medical Records: Documentation of the patient’s treatment can help establish what actions were or were not taken.

Why Duty of Care is Crucial in Ontario Medical Malpractice Cases

The duty of care is a legal bond between patient and provider, meant to ensure safety and proper medical practice. When this duty is breached, it can lead to significant physical, emotional, and financial consequences for patients. Understanding these principles is crucial for anyone involved in or considering a medical malpractice lawsuit in Ontario.

Here to Assist with Your Claims

At Nelligan Law, we understand the complexities of medical malpractice in Ontario. Our experienced team is committed to handling your case with the sensitivity and dedication it deserves. Contact us for expert guidance and support throughout your medical malpractice claim process.

Read More About
Related Categories

Full Range of 
Legal Expertise

Explore practical articles, guides, and resources designed to help you understand legal issues, stay informed, and feel confident about your next steps.
Boating Accidents in Ontario: Understanding Liability on the Water

Boating is a favourite summer pastime of Ontarians and we are lucky to have many beautiful lakes and rivers

Continue Reading

Voluntary Departure Packages: What to Know Before You Decide

Recent media coverage has drawn renewed attention to voluntary departure packages, sometimes called buyouts. In April 2026, CBC News

Continue Reading

Malini Vijaykumar on CTV’s Ask the Expert: Severance, Toxic Workplaces, and the Risks of “DIY” Legal Advice

Malini Vijaykumar joined CTV’s Ask the Expert this week to discuss workplace rights, especially in today’s uncertain economic climate.

Continue Reading

Legal challenges can be overwhelming - 

we're here to guide you forward.

Start the conversation with a team that puts your needs first.

Choose the area of law you need help with, or select ‘I’m not sure’ if you’re uncertain.
Tell us a bit about your situation in general terms. Note that sending us a message doesn’t mean we’re officially working together yet, so if you’re not already a client, please don’t include confidential or sensitive information.