LAWYER PROFILE
Patrick Duffy

Patrick Duffy

Global 2026

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Ranked in 2 practice areas

About

Provided by Stikeman Elliott LLP

Practice Areas

Patrick Duffy is a partner and Co-Head of the Projects & Infrastructure Group. His practice focuses on project development that includes municipal and planning law, environmental permitting and litigation, energy regulation, and Indigenous engagement. He is highly sought after for his considerable experience with environmental assessments and other regulatory approvals in a variety of sectors, including renewable and non-renewable electricity generation, electricity transmission, mining, transit and transportation, aggregate quarries, and waste management. Patrick also advises clients in responding to environmental inspections, investigations and prosecutions at both the provincial and federal levels.

Patrick is an experienced advocate and has appeared before the Supreme Court of Canada, the Federal Court of Canada, all levels of courts in Ontario and a variety of administrative tribunals, including regular appearances before the Ontario Energy Board and the Ontario Land Tribunal. He has acted for both provincial and municipal governments and many of his mandates involve administrative or public law issues, including issues related to public and Indigenous engagement.

Patrick is known for his strength in advising on the business interests of energy clients and handling the full gamut of regulatory proceedings in connection with the development of energy projects. He also has expertise in public procurement processes and has been involved in all stages in a number of sectors on both the customer and bidder side. He helps draft the terms of public procurements, assists proponents in responding to procurements, and represents proponents in procurement-related litigation.

Chambers Review

Provided by Chambers

Chambers Global Guide

Energy: Power (Regulatory) - Canada

Band 3
Band 3

Individual Editorial

Based in Toronto, Patrick Duffy advises on environmental assessments and contamination issues, alongside his broader focus on project development and energy regulatory matters. He has experience appearing before the Environmental Review Tribunal.

Environment - Canada

Band 3
Band 3

Individual Editorial

Based in Toronto, Patrick Duffy advises on environmental assessments and contamination issues, alongside his broader focus on project development and energy regulatory matters. He has experience appearing before the Environmental Review Tribunal.

Strengths

Provided by Chambers

  • He is an impressive counsel and advocate.

    Energy: Power (Regulatory)Chambers Global Guide
  • Patrick is very knowledgeable and knows everybody in the sector.

    Energy: Power (Regulatory)Chambers Global Guide
  • Patrick is very practical.

    Energy: Power (Regulatory)Chambers Global Guide
  • Patrick provides excellent service and responsiveness.

    Energy: Power (Regulatory)Chambers Global Guide
  • Patrick is a real pleasure to work with, not only for his expertise in environmental matters, but for his commercial approach to problem-solving.

    Energy: Power (Regulatory)Chambers Global Guide

Ranked Individuals at Stikeman Elliott LLP (82)

Canada

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