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Mahmud Jamal - Commercial Litigation Lawyer

Mahmud Jamal

Partner, Litigation

Key Contact: Competition/Antitrust Litigation

Contact Information

tel: 416.862.6764



Bar Admission

Ontario, 1996

  • Yale Law School, LL.M. (Fulbright Scholar)
  • McGill University, LL.B. and B.C.L.
  • University of Toronto, B.A.
English, French

Mahmud Jamal’s national litigation practice includes the defence of class actions, banking litigation, constitutional and administrative law, aboriginal litigation, competition/antitrust, pension, tax, copyright and other regulatory litigation. He has argued thirty-five appeals before the Supreme Court of Canada as counsel to a party or intervener in a wide range of civil, constitutional, criminal, and regulatory areas. He has also argued cases at all levels of court in Ontario, British Columbia, Alberta, Quebec, New Brunswick, Newfoundland and Labrador, at the Federal Court and Federal Court of Appeal, and before federal and provincial administrative tribunals such as the Competition Tribunal, the Ontario Energy Board, and the Financial Services Tribunal. He is a former law clerk to the late Mr. Justice Charles D. Gonthier of the Supreme Court of Canada and to Mr. Justice Melvin L. Rothman of the Quebec Court of Appeal. Mahmud is bilingual and has litigated trials and appeals conducted in French.

Mahmud is a member of the firm’s Executive Committee, which oversees the overall strategic direction of the firm.

Numerous industry publications describe Mahmud as being widely regarded by clients and peers as one of Canada’s top litigators in the areas of class actions defence, competition litigation, commercial litigation, Supreme Court and appellate advocacy, and constitutional and administrative law:

  • Chambers Global (2015) notes that Mahmud “is well regarded for his public law, constitutional law, competition and banking litigation expertise. One source said: "He's a very, very smart guy. He has that raw intelligence but also the analytical skills and ability to break down tough problems.””
  • Benchmark Litigation Canada (2015) describes Mahmud as “a peer and client favorite, as well as, it is observed, a favorite of judges, in the class actions space. “If a brief comes through with Mahmud’s name on it, judges will show a rare level of deference”” and notes that “his ethics and intellectual acumen are unassailable;”  "widely touted for his handling of a variety of commercial litigation matters, focusing primarily on class-action defence work" and ""commands respect from bench and bar alike", enthuses a peer. "I have personally witnessed judges express delight when they come across a file with Mahmud's name on it"" (2014); ""a stellar thinker and he is taking Oslers' class-action practice to a national platform"" (2013).
  • Martindale-Hubbell ranks Mahmud as AV Preeminent, its highest rating, and quotes client and peer research describing him as “a top drawer lawyer with a superb Supreme Court of Canada practice” and as “courteous and very professional.”

Mahmud is also regularly listed for litigation expertise in various categories in The Best Lawyers in Canada, the Canadian Legal Lexpert Directory, Lexpert’s Special Edition on Canada’s Leading Litigation Lawyers, and Lexpert’s Guide to the Leading US/Canada Cross-Border Litigation Lawyers in Canada.

    • Imperial Tobacco Canada Limited before the Quebec Court of Appeal successfully overturning a $1.13 Billion order of provisional execution in two class actions: Imperial Tobacco Canada Ltd. v. Conseil québécois sur le tabac et la santé, 2015 QCCA 1224.
    • Bank of Montreal before the B.C. Supreme Court and Court of Appeal in a class action involving credit card merchant fees: Watson v. Bank of America Corporation et al., 2014 BCSC 532, appeal to B.C.C.A. (argued December 2014).
    • Amex Bank of Canada before the B.C. Supreme Court and Saskatchewan Court of Queen’s Bench in a proposed class action involving pre-paid payment cards (ongoing).
    • J.D. Irving Ltd. before the New Brunswick Court of Queen’s Bench and Court of Appeal resisting an injunction brought by Aboriginal peoples alleging a breach of the duty to consult in the forestry sector: Chief Mary Ann Simon et al. v. Province of New Brunswick et al., 2014 CanLII 59594 (N.B.C.A.).
    • Amex Bank of Canada, Bank of Montreal, Bank of Nova Scotia, CIBC, Citibank, Laurentian Bank, National Bank, Royal Bank, and TD Bank before the Quebec Superior Court, Court of Appeal, and the Supreme Court of Canada challenging the constitutional applicability of the Quebec Consumer Protection Act to bank-issued credit cards: Marcotte v. Bank of Montreal, 2009 QCCS 2764; 2012 QCCA 1396; 2014 SCC 55; and Adams v. Amex Bank of Canada, 2009 QCCS 2695; 2012 QCCA 1394; 2014 SCC 56.
    • Various companies (including General Motors of Canada Limited, NEC Corporation and NEC Canada) in several competition/antitrust class actions before courts in Ontario, B.C., Manitoba, Quebec, and Saskatchewan.
    • RBC Life, BMO Life and Industrial Alliance before the Federal Court and Federal Court of Appeal successfully quashing four ex parte requirements issued under the Income Tax Act compelling the disclosure of confidential client information: 2011 FC 1249; 2013 FCA 50.
    • Shoppers Drug Mart before the Ontario Divisional Court, Court of Appeal, and Supreme Court of Canada challenging a regulation banning private label generic drugs: Shoppers Drug Mart Inc. v. Ontario, 2011 ONSC 615 (Div. Ct.); 2011 ONCA 830; 2013 SCC 64.
    • Canadian Bankers Association before the Competition Tribunal dismissing allegations that Visa and MasterCard’s system rules constitute price maintenance: Commissioner of Competition v. Visa Canada Corp. and MasterCard International Inc., 2013 Comp. Trib. 10; before the Supreme Court of Canada, Quebec Court of Appeal, and Alberta Court of Appeal in federal and provincial references to determine the constitutionality of the federal Parliament creating a national securities regulator: Reference re Securities Act, [2011] 3 S.C.R. 837 (Identified by Lexpert as one of the “Top 10 Business Cases from 2012”); 2011 QCCA 591; 2011 ABCA 77; and before the Supreme Court of Canada in an appeal dealing with the relationship between pensions and insolvency law: Sun Indalex Finance v. United Steelworkers, 2013 SCC 6 (Identified by Lexpert as one of the “Top 10 Business Cases from 2013”).
    • Ontario Energy Board Staff before the Ontario Energy Board in a constitutional challenge to Ontario’s green energy assessments under the Ontario Energy Board Act (EB-2010-0184); and the Ontario Energy Boardin quashing summons to compel Board members to testify in regulatory proceedings: Summit Energy Management Inc. v. Ontario Energy Board, 2012 ONSC 2753 (Div. Ct.).
    • Re:Sound before the Supreme Court on Canada in a copyright appeal: Re:Sound v. Motion Picture Theatre Associations of Canada, 2012 SCC 38(Identified by Lexpert as one of the “Top 10 Business Cases from 2012”).
    • Greater Toronto Airports Authority in two appeals before the Supreme Court of Canada to defend federal jurisdiction over aeronautics:Quebec (Attorney General) v. Canadian Owners and Pilots Association, [2010] 2 S.C.R. 536; Quebec(Attorney General) v. Lacombe, [2010] 2 S.C.R. 453; in appeals relating to the taxation of airport tenants: Exchange Corporation Canada v. Mississauga et al, 2012 ONSC 6221 (Div. Ct.), appeal dismissed 2014 ONCA 113; Clear Channel Outdoor Communication Canada v. Municipal Property Assessment Corporation, 2013 ONSC 7014 (Div. Ct.); in a judicial review to secure Pickering Airport lands: GTAA and Attorney General of Canada v. Berrywoods Farms(2006), 208 O.A.C. 82, 19 M.P.L.R. (4th) 293 (Ont. Div. Ct.); resisting an injunction in connection with tender process: Airport Limousine Drivers Association v. Greater Toronto Airports Authority, [2005] O.J. 3510 (S.C.J.), lv. to appeal dismissed; in an appeal on the legality of airport rates and charges: Air Canada v. Greater Toronto Airports Authority(2000), 130 O.A.C. 81 (C.A.)); in a leading case on the constitutional applicability of provincial laws to airports: GTAA v. Mississauga (2000), 50 O.R. (3d) 641 (C.A.), lv. to appeal to S.C.C. dismissed.
    • Privacy Commissioner of Canada before the Supreme Court of Canada in appeals affecting the privacy rights of Canadians: Wakeling v. Attorney General of Canada, 2014 SCC 72 (constitutionality of sharing wiretap information with foreign law enforcement authorities); R. v.Spencer, 2014 SCC 43 (constitutionality of police requesting ISP subscriber information without a warrant); Alberta (Information and Privacy Commissioner) v. United Food and Commercial Workers, Local 401, 2013 SCC 62 (challenge to Alberta’s privacy legislation under s. 2(b) of Charter).
    • Dell Canada Inc. before the Supreme Court of Canada in a case dismissing a consumer class action in favour of arbitration: Dell v. Union des consommateurs, [2007] 2 S.C.R. 281 (Identified by Lexpert as the most important case affecting business in Canada from 2007 in its feature “Top 10 Business Cases of 2007”); and in a product liability class action: Griffin v. Dell Canada Inc., 2009 CanLII 18222 (S.C.), appeal dismissed 2010 ONCA 29; case settled: 2011 ONSC 3292.
    • Nalcor Energy before Newfoundland and Labrador Trial Division successfully resisting an injunction brought by aboriginal group alleging breach of the Crown’s duty to consult in relation to Lower Churchill River hydroelectric project: Nunatukavut Community Council Inc. v. Newfoundland and Labrador Hydro-Electric Corporation (Nalcor Energy), 2011 NLTD 44.
    • Imperial TobaccoCanada Ltd. before the New Brunswick Court of Queen’s Bench and Court of Appeal in challenging a contingency fee agreement concluded by the province’s Attorney General: Imperial Tobacco v. New Brunswick (Attorney General), 2010 NBCA 35; 2009 NBQB 198.
    • Dollar Financial Group, Inc. in motions, trials and appeals in Ontario and British Columbia involving the relationship between arbitration and class actions. Mackinnon v. National Money Mart, 2009 BCCA 103 and Smith Estate v. National Money Mart Co., 2008 ONCA 746.
    • Tax litigation before the Federal Court, Federal Court of Appeal, and the Supreme Court of Canada:Canada (Minister of National Revenue) v. Welton Parent, [2006] F.C.J. 117 (F.C.)(actuarial firm challenging requirements under the Income Tax Act); Placer Dome v. Ontario (Ministry of Finance), 2006 SCC 20, rev’g (2004), 190 O.A.C. 157 (C.A.)(taxation of hedging and financial derivatives under the Mining Tax Act); Rezek v. Canada, [2005] 3 C.T.C. 241 (Fed. C.A.), lv. to S.C.C. dismissed (taxation of convertible hedging under Income Tax Act); and Gifford v. Canada, 2004 SCC 15 (interest deductibility).
    • New Brunswick Forest Products Association in aboriginal rights and treaty litigation before the Supreme Court of Canada: R v. Sappier and Polchies; R. v. Gray, 2006 SCC 54;and R. v. Marshall; R. v. Bernard, 2005 SCC 43.
    • Canadian Bar Association before the Supreme Court of Canada to protect solicitor-client privilege: Minister of National Revenue v. Thompson, SCC 35590 (privilege in the income tax context) (argued December 4, 2014); Ontario v. Criminal Lawyers’ Assn., 2010 SCC 23 (whether government must abrogate privilege to promote freedom of expression); Privacy Commissioner of Canada v. Blood Tribe Department of Health, 2008 SCC 44 (whether regulators can abrogate privilege) (Identified byLexpert as one of the “Top 10 Business Cases of 2008”); Celanese Canada Inc. v. Murray Demolition Corp., 2006 SCC 36 (removal of counsel for abrogating privilege); and regarding the content of a court’s duty to give reasons: Cojocaru v. British Columbia Women's Hospital and Health Center, 2013 SCC 30.
    • Canadian Civil Liberties Association before the Supreme Court of Canada to protect civil liberties under the Charter: Attorney General of Canada v. Federation of Law Societies of Canada, 2015 SCC 7 (federal anti-money laundering legislation infringing solicitor-client privilege); R. v. Chehil, 2013 SCC 49 (privacy); R. v. MacKenzie, 2013 SCC 50 (privacy); Canadian Broadcasting Corp. v. The Queen, 2011 SCC 3 (press freedom); Canadian Broadcasting Corp. v. Canada (Attorney General), 2011 SCC 2 (press freedom); Alberta v. Hutterian Brethren of Wilson Colony, 2009 SCC 37 (freedom of religion); R. v. Bryan, 2007 SCC 12 (free expression); and Multani v. Commission scolaire Marguerite-Bourgeoys, 2006 SCC 6 (freedom of religion). 

  • Chambers Canada: Canada’s Leading Lawyers for Business, 2017, recognized in the area of Dispute Resolution: Class Action (Defence). 
    • "He is certainly regarded as being exceptionally bright. He's very focused and writes extremely well. He's on all of the major cases, he takes a leading role in drafting documents and he has a strong presence in court."
  • Chambers Canada: Canada’s Leading Lawyers for Business, 2016-2017, recognized in the area of Dispute Resolution: Ontario.
  • Chambers Global 2016: Dispute Resolution (Ontario)
  • Benchmark Litigation Canada 2016: Class Actions; Competition; Constitutional; General Commercial; Tax
  • The Best Lawyers in Canada 2016: Corporate and Commercial Litigation; Administrative and Public Law Litigation
  • Martindale-Hubbell, AV Preeminent (highest category)
  • The Canadian Legal Lexpert Directory 2016: Public Law Litigation (Most Frequently Recommended); Litigation-Corporate Commercial (Consistently Recommended) and Class Actions (Repeatedly Recommended)
  • Lexpert’s Guide to the Leading US/Canada Cross-Border Litigation Lawyers in Canada (2014)
  • Lexpert’s Special Edition on Canada’s Leading Litigation Lawyers (2014)
  • Lexpert Zenith Award (Platinum) (2010): for pro bono litigation involving freedom of religion
  • Lexpert’s Top 40 Lawyers Under 40 in Canada (2004)
  • Canadian Who’s Who

  • Chair of Osler’s Pro Bono/Community Law Committee
  • Canadian Civil Liberties Association, Vice-President and Member, Board of Directors
  • Osgoode Society for Canadian Legal History, Counsel to the Board of Directors
  • Canadian Business Law Journal, Trustee
  • National Journal of Constitutional Law, Member of the Board of Editors
  • Canadian Bar Association and Canadian Civil Liberties Association, Pro Bono Counsel

  • Advocacy Advisor, Supreme Court Advocacy Institute
  • American Bar Association, Litigation and Antitrust Sections
  • Canadian and Ontario Bar Associations
  • Reviewable Matters and Private Actions Committee, Canadian Bar Association, Competition Law Section
  • Advocates’ Society

Teaching (selected)

  • Osgoode Hall Law School, Lecturer (Administrative Law Remedies) and co-Director, Administrative Law LL.M. Program
  • University of Toronto Law School, past guest instructor, Class Actions
  • University of Ottawa Law School, past guest instructor, Constitutional Litigation
  • University of British Columbia Law School, past guest instructor, Banking and Constitutional Litigation
  • McGill Law School (Comparative Constitutional Law), Former Lecturer
  • Ontario Bar Admission Course, past instructor, Public Law

Publications (selected)

  • The Charter of Rights in Litigation (2 vols., loose-leaf), Canada Law Book, 2001+ (co-author)
  • “Dissents and Concurrences: Seven Debates in Charter Jurisprudence” (co-author) (2013), 63 S.C.L.R. (2d) 89-110
  • Reference re Securities Act”, in What’s Next for Canada?: Securities Regulation After the Reference (2012), ed. Anita Anand, pp. 95-101
  • “The Supreme Court of Canada and Solicitor-Client Privilege: What Every Practitioner Needs to Know”, paper delivered to the Canadian Bar Association (2007, 2008, 2013) and the Association of Corporate Counsel (2014)
  • “Recent Developments in Freedom of Religion” (2009), 27 N.J.C.L. 253-261
  • “Non-Charter Constitutional Law Developments, 2007-2008” (2008), N.J.C.L. 59-69
  • “Recovering Unlawful Taxes After Kingstreet Investments”, in Unjust Enrichment: Emerging Jurisprudence (ed. G. Radhika), 2008, pp. 181-195
  • “”Everything Else”: Non-Charter Constitutional Developments, 2006-2007” (2007) 23 N.J.C.L. 21-41
  • “Is PIPEDA Constitutional?” (2006) 43 Can. Bus. L.J. 434-454
  • “Treaty Interpretation After R. v. Marshall; R. v. Bernard” (2006), 34 S.C.L.R. (2d) 443-463
  • “Freedom of Religion in the Supreme Court: Some Lessons from Multani” (2006) 21 N.J.C.L. 291-312
  • “Recent Developments in Section 1 of the Charter” (2005), 19 N.J.C.L. 141-154
  • “Constitutional Issues in Canadian Competition Litigation” (2004-2005), 41 Can. Bus, L.J. 66-102
  • “Legislative Facts and Charter Litigation: Where Are We Now?” (2004), 17 N.J.C.L. 1-18
  • “The Misquadis Case”, in Legal Aspects of Aboriginal Business Development (2005), ed. J.E. Magnet and D.A. Dorey, pp. 123-136
  • “Class Actions and Aboriginal Litigation” (co-author), in Aboriginal Rights Litigation (2003), ed. J.E. Magnet and D.A. Dorey, pp. 293-320
  • “The Constitutionalization of Solicitor-Client Privilege” (co-author) (2003), 20 S.C.L.R. (2d) 213-247