Liane Langstaff

Liane Langstaff is an environmental lawyer in Gowling WLG's Toronto office. She draws upon her B.Sc. in Environmental Sciences, her MBA and law degree to provide strategic regulatory advice and representation to her corporate and municipal clients.

Liane is a problem solver. She relishes the challenge of distilling complex legislation, translating the opinions of expert scientists and land-use planners for judges, and crafting persuasive legal arguments to help her clients succeed before courts and tribunals.

Liane frequently acts on cutting-edge environmental and legal issues, including environmental assessments, species at risk, climate change and constitutional law. She helped the Canadian Public Health Association intervene in the Greenhouse Gas Pollution Pricing Act constitutional cases before the Courts of Appeal of Ontario, Alberta, and Saskatchewan, as well as the Supreme Court of Canada. As a member of the firm's ESG Advisory Service practice and as a Climate Governance Expert with the Canada Climate Law Initiative, Liane advises on the risks and opportunities associated with climate change and biodiversity.

As an accomplished speaker and teacher, Liane has provided her insights to the Governance Professionals of Canada, Women Get on Board and the Ontario Bar Association. She has also served as a past co-instructor of the environmental law course at Osgoode Hall Law School. She writes extensively on the latest developments in environmental law as a regular contributor to Gowling WLG's environmental law newsletter, co-author of A Guide to Canada's Impact Assessment Act, 2020 Edition and as an author for a chapter in A Business Guide to Environmental Law.

Liane honed her legal skills as a clerk at the Ontario Court of Appeal. She graduated from Osgoode Hall Law School and the Schulich School of Business, where she was awarded the Joseph-Armand Bombardier Scholarship and Hennick Medal for Academic Excellence.

Associations professionnelles

  • Ontario Bar Association
  • Canadian Bar Association
  • Climate Change Lawyers Network

Liane is a regular contributor to Gowling WLG's Environmental Law Newsletter. In addition to those articles, Liane has contributed to the following publications and given the following presentations and lectures:


Co-author, A Guide to Canada's Impact Assessment Act, 2020 Edition, LexisNexis Canada (March 2020)

Contributor on Canadian climate change law in David Estrin's Business Guide to Environmental Law (2016 update)

Media mentions

  • Featured in the Institute of Corporate Directors' August 2023 edition of Director Journal on the topic of biodiversity in article "Getting Back to Nature"

Presentations, lectures and teaching

  • Speaker, "Environmental Law Year in Review 2020: Current Trends in Climate Change Regulation and Mitigation", Gowling WLG Webinar (November 2020)

  • Speaker, "ThinkHouse Unlocked : Climate Change Litigation", Gowling WLG UK Webinar (September 2020)

  • Speaker, "ESG and the Role of the Board", Women Get on Board National Webinar (June 2020) and Toronto Live Event (February 2020)

  • Speaker, "Bracing for the Storm: Climate Litigation Risk", Canada Climate Law Initiative, Vancouver (February 2020)

  • Moderator & Panel Chair, "Climate Inaction on Trial: The Future of Litigation, Youth Advocacy and Industry Response", Globe Conference, Vancouver (February 2020)

  • Guest Lecturer, "Environmental Tribunals and Boards", School of Planning, University of Waterloo (2019 and 2020)

  • Co-Instructor, Environmental Law, Osgoode Hall Law School, York University (Fall 2019 semester)

  • Speaker, "Environmental Law for Business: A Year in Review" (November 2019)

  • Guest Lecturer, "Renewable Energy Projects with Northern Ontario First Nations: Considerations, Challenges and Solutions", Lecture and Aboriginal Law Simulation Negotiation, Osgoode Hall Law School, York University (January 2016) and Bora Laskin Faculty of Law, Lakehead University (November 2016)

Mandats représentatifs

Client work highlights

Liane has appeared before the Superior Court of Justice on contaminated lands disputes as well as land-use planning and cultural heritage matters. She has experience managing technical experts and navigating administrative tribunal proceedings, including the Environmental Review Tribunal (ERT) and federal Panels convened under the Canadian Environmental Assessment Act. She has assisted her clients in mediations, settlement conferences and international arbitrations.

Representative work

  • Assisted municipalities as well as mining and aggregate resources companies navigate federal and provincial environmental assessments, including representing clients in hearings before federal panels convened under the Canadian Environmental Assessment Act;
  • Ensured international companies could do business in Canada by advising them on how to comply with complex chemical, waste management and product stewardship regulations;
  • Represented municipalities, energy companies and dry cleaners on contaminated lands litigation, as both plaintiffs and defendants;
  • Acted for municipal and corporate clients on regulatory investigations and enforcement, including matters before the Environmental Review Tribunal;
  • Drafted agreements to protect clients from environmental liabilities, allocate ownership of carbon credits and establish carbon reporting and disclosure requirements; and
  • Advised municipal clients on land-use planning, zoning and cultural heritage conservation matters, and brought cases to the Superior Court of Justice to clarify land-use planning law.

Selected Decisions

  • Reference re: Greenhouse Gas Pollution Pricing Act2019 SKCA 402019 ONCA 5442020 ABCA 74 (Courts of Appeal of Saskatchewan, Ontario and Alberta)
  • Oakville (Town) (Re)2021 CanLII 1129 (Ont Information and Privacy Commissioner)
  • CAMPP Windsor Essex Residents Association v Windsor (City)2020 ONSC 4612 (Ont Divisional Court)
  • Tre Memovia Developments Ltd. v 1491316 Ontario Inc.2019 ONSC 4, upheld on appeal 2020 ONSC 1568 (Ont Superior Court of Justice) and upheld at the Divisional Court.
  • Wiggins v Ontario (Environment and Climate Change)2016 CanLII 67372 (Ont Environmental Review Tribunal)