Heather L. Treacy K.C. ICD.D.
PartnerCo-chair, Canadian Litigation Group
Heather L. Treacy, K.C. is a highly sought after and nationally recognized counsel whose practice is focused on civil litigation and dispute resolution.
Heather is the former Managing Partner of the Calgary office of DLA Piper (2013-2019) and a former elected member of DLA Piper’s Executive Committee. She has over 30 years of experience in acting as counsel to clients in complex multi-party litigation and disputes, and has extensive experience with negotiations and mediation on matters related to tort law, class actions, energy and resources law, indigenous and constitutional law, general commercial disputes, transportation, aviation, products liability, human rights, employment law, health law and intellectual property law. She frequently appears before both the Trial and Appellate Courts in the Province of Alberta, the Federal Court of Canada, the Federal Court of Appeal and various tribunals, including the Canadian Human Rights Tribunal, energy related tribunals and the Canadian Transportation Agency. In addition to the above, Heather provides legal and governance advice to both public and private sector boards. Heather also chairs the pro bono committee of DLA Piper.
Heather also has specific expertise in indigenous law and provides advice on a significant number of issues involving treaty, indigenous rights and indigenous title issues and has been involved in several precedent setting cases, including those in the energy sector.
Heather has been recognized for her expertise in the area of dispute resolution by leading lawyer ranking guides Benchmark Canada (Litigation Star), Acritas (Star Lawyer), Chambers Canada, Legal 500 Canada and Euromoney. In the area of indigenous law, she has been recognized by The Canadian Legal Lexpert Directory, Best Lawyers in Canada, Chambers Global and Chambers Canada. In 2014, Heather was named one of WXN’s Top 100, Canada’s Most Powerful Women, in 2016, she was a Women in Law Leadership (WILL) Award winner in the “Leadership in the Profession in Private Practice” category, and in 2017 she was named a winner of the Lexpert Zenith Awards: Celebrating Women in Law. Most recently, Heather was an Excellence Award Recipient in the Woman of the Year category for the 2020 Canadian Law Awards.
Heather is active in the community and has a passion for the arts. She is the former Chair of the Board of Directors of the Calgary Philharmonic Orchestra. She is a former member of the Board of Directors of the University of Calgary Alumni Association. She a former member of the Board of Directors of the Calgary International Language Foundation and currently a member of the Board of Directors of the Calgary French and International School Society.
EXPERIENCE
- Acting as counsel for a financial institution in relation to claims advanced by 135 Plaintiffs related to their RRSP, TFSA and RRIF investments (Andersen v CWT et al).
- Defending a pharmaceutical company in a class action lawsuit involving the sale and marketing of opioids.
- Defended an educational institution in a class action involving allegations of sexual assault.
- Acting as counsel for an energy company on claims related to its patents and royalties.
- Acting as counsel on various employment related disputes involving allegations of harassment and discriminating conduct.
- Acting as counsel for energy companies on claims involving royalty calculation issues (Stoney Tribal Council v Petro-Canada Ltd. et al).
- Acted as counsel for a public school board in relation to a judicial review application associated with a student lottery admission process (Meyer v CBE).
- Acting as counsel for a manufacturer in relation to a products liability claim involving agricultural feed products.
- Acted as counsel for an international air carrier in proceedings advanced by multiple passengers before the Canadian Transportation Agency and the Federal Court of Appeal (Swiss International Air Lines Ltd. v CTA et al).
- Acted as counsel to a manufacturing company involving the protection of its trademark and intellectual property.
- Acted as counsel in successfully compelling that an election be held when cancelled by a First Nations government (Shotclose et al v Stoney First Nation et al).
- Acted as Chief Federal Negotiator for the Government of Canada in a treaty on Vancouver Island involving the B.C. treaty process for First Nations.
- Co-Counsel for Imperial Oil in its application for the Kearl Oil Sands Project before a Joint Review Panel established by the Alberta Energy and Utilities Board and Canadian Environmental Assessment Agency.
- Acted on trespass and royalty claims arising out of the production of oil and gas on reserve lands (Samson Indian Band et al v Imperial Oil et al).
- Acted as counsel for a financial institution involving an action to trace and recover funds based on allegations of bribery (Alberta Treasury Branches v Leahy et al).
- Acted as counsel defending a manufacturer of helicopter parts in relation to a products liability claim.
- Acted as counsel in Federal Court to constitutional challenges to customary aboriginal laws (Letendre v Appeal Board of the Horse Lake First Nations; Ashley Paige Horseman v Horse Lake First Nation).
- Acted on injunctive relief and membership issues associated with a First Nation Community (Horseman v Horse Lake First Nation).
- Acted as counsel on a matter as to whether an immigrant who was “overqualified” for a position of employment was discriminated on the basis of national or ethnic origin (Sangha v McKenzie Valley Land and Water Board).
- Acted as counsel for an international air carrier in obtaining Anton Piller relief.
- Acted on issues associated with the specific land claim agreement of a First Nation Community (McAllister v Horse Lake First Nation).
- Acted on determination of reserve interests under Indian Act (Stoney Band v Poucette).
- English
- Institute of Corporate Directors, University of Toronto Rotnam School of Management and Haskayne School of Business, ICD.D. (May 2018)
- LL.B., University of Alberta, 1989
B.Comm, B. PE University of Calgary, 1984
Music Degrees, Royal Conservatory of Toronto and Mount Royal University, 1984
Awards
- Thomson Reuters’ Stand-out Lawyer, 2022
- Best Lawyers in Canada (Aboriginal/Indigenous Law), 2012-2025; (Energy Law), 2023-2025; (Natural Resources Law), 2024-2025; (Labour & Employment Law), 2025; (Alternative Dispute Resolution Law), 2025
- Excellence Award Recipient, The Gowling WLG Award for Woman of the Year,Canadian Law Awards, 2020
- Winner of the Lexpert Zenith Awards: Celebrating Women in Law, 2017
- Winner of the Women in Law Leadership (WILL) Awards in the "Leadership in the Profession in Private Practice” category, 2016
- Recognized as one of Canada's Most Powerful Women: Top 100 WXN, 2014
- Litigation Star, Benchmark Canada , 2014-2024
- Listed as Acritas Star™ Lawyer 2019-2020
- Canadian Legal Lexpert® Directory (Aboriginal Law), 2010-2018, 2020-2024
- Euromoney’s Expert Guides (Litigation and Product Liability) 2016
- Chambers Canada (Aboriginal Law), 2016-2025; (Litigation: General Commercial - Alberta), 2018-2025
- Chambers Global (Aboriginal Law), 2015, 2022, 2024
- The Legal 500 Canada (Dispute Resolution), 2016-2025; (Indigenous Law), 2018-2024
- Martindale-Hubbell, Distinguished® Peer Review Rated
- Received the distinction and recognition as Queen's Counsel in 2012
- Recipient of the 1996 Canadian Bar Association Young Lawyers Pro Bono Service Award
Seminars
- Panelist, "How Today’s Leaders are Redefining Success and Breaking New Boundaries," The Canadian Law Awards, October 6, 2020
- Speaker, "First Nations Law: Update on Recent Developments", Calgary Energy Sector Speaker Series, Oct 15, 2015
Media Mentions
Quoted, "A Winding Path for Pipelines", Lexpert Special Edition - Energy, October 2017
Quoted, "Reconciliation Time", Lexpert, June 2016
Community Involvement
- Member of the Board of Directors and co-Chair of the Governance Committee of the Calgary French and International School Society
- Past Member of the Board of Directors of the Calgary International Language Foundation
- Past Member of the Board of Directors and Governance and Nominating Committee of the University of Calgary Alumni Association
- Past Chair, Vice-Chair of the Board, and Past Chair, Governance Committee and member of the Board of Directors of the Calgary Philharmonic Orchestra
- Alumni Representative, The University of Calgary Energizing Eyes High Strategic Planning Committee (2016 to 2017)
- Past member, Board of Directors and Corporate Secretary of the Alberta Ballet Company
- Past member, Board of Directors of Theatre Junction
- Past member, Calgary Region Arts Foundation
Memberships And Affiliations
- Law Society of Alberta
- Calgary Bar Association
- Canadian Bar Association
- International Bar Association
- Association of International Petroleum Negotiators
- Institute of Corporate Directors
- Former Member of the Professional Responsibility Committee of the Law Society of Alberta, 2008 to 2014
- Former Member of the Law Society of Alberta Pro Bono Committee, 2007-2008
- Former Member of the Law Society of Alberta Civil Practice Advisory Committee, 2004-2007
- Executive Member of the National Aboriginal Law Section of the Canadian Bar Association
- Past Chair, Vice-Chair and Secretary-Treasurer of the Aboriginal Law Section (Southern Alberta) of the Canadian Bar Association
- Past Chair of the Constitutional Law Section (Southern Alberta) of the Canadian Bar Association
