Margarita Mercado

Margarita has more than 15 years of experience as a litigator.  She has focused her career on commercial and constitutional litigation, appellate advocacy, regulatory affairs, and professional ethics, and has unique expertise in energy issues.  She has advised and represented clients in a comprehensive array of matters, including insurance, energy and compliance, torts, contracts, medical malpractice, banking, public bids and procurement processes, compliance with federal consent decree, antitrust law, and professional conduct and ethics.

Margarita has argued six cases before the Puerto Rico Supreme Court and eleven before the United States Court of Appeals for the First Circuit. 

Since 2017, Margarita is an adjunct professor of law at the University of Puerto Rico Law School. She teaches legal research and writing, appellate practice and supervises third-year law students representing clients in legal ethics proceedings before the Puerto Rico Supreme Court. 

Margarita has also served as a member of the Advisory Committee on Rules and the Selection Committee for the Criminal Justice Act Panel for the U.S Court of Appeals for the First Circuit. Since 2016, Margarita has been a member of the District Examination Committee of the United States District Court for the District of Puerto Rico, designated by the District Court. 

Commonwealth of Puerto Rico v. Sánchez Valle, Case No.15-108, before the United States Supreme Court, 136 S. Ct. 28 (June 9, 2016). Co-litigated case that presented the question whether the Commonwealth of Puerto Rico and the federal government are separate sovereigns for double jeopardy purposes.

California Tax Free Trust, et al. v. Commonwealth of Puerto Rico, et al, Case No. 15-233, before the United States Supreme Court, 136 S. Ct. 1938 (June 13, 2016). Co-litigated case that presented the question whether Chapter 9 of the United States Bankruptcy Code preempted a Puerto Rico statute that allowed Puerto Rico’s public corporations and municipalities to restructure their debts.

Ada Conde et al v. Ríus Armendáriz et al, Appeal Nos. 14-2184; 16-1313, before the U.S. Court of Appeals for the First Circuit, 818 F.3d 765 (1st Cir. 2016). Represented the Commonwealth of Puerto Rico in controversy regarding the constitutionality of Puerto Rico’s marriage law and successfully advocated in favor of a judicial determination that the Commonwealth statute was unconstitutional as it discriminated against same sex couples. Defended enforceability of the First Circuit’s judgment declaring Puerto Rico’s marriage law unconstitutional.

ECP Inc. v. Office of the Commissioner of Insurance of Puerto Rico (OIC), 2020 TSPR 112 (September 24, 2020), obtained favorable ruling from the Puerto Rico Supremo Court on behalf of ECP Inc., to annul administrative investigation over manufacturer’s warranties that the OIC conducted outside the scope of its legal authority.

Bhatia Gautier v. Rosselló, Adversary Proceeding 17-136, BK 17-3283 (LTS), before ethe U.S. District Court for the District of Puerto Rico. Obtained favorable ruling remanding to Commonwealth court a Mandamus Petition for access to public information.

Bhatia v. Rosselló, 199 DPR 59 (2017), represented Puerto Rico Senator in Puerto Rico local courts, in mandamus action requesting disclosure to the Government’s draft budget. Favorable ruling from the Puerto Rico Supreme Court holding that the Senator had standing and that the case was not moot. On remand, obtained favorable judgment on the merits, requiring the Government to disclose de draft budget.

Pueblo v. Pablo Casellas, Appeal No. AC-2016-006, favorable opinion issued on April 25, 2017 by the Puerto Rico Supreme Court in appeal to request vacatur of order granting appellee a new criminal trial. Argued that the 6th Amendment requirement of a unanimous jury verdict does not apply to Puerto Rico.

Torres Montalvo v. García Padilla, Case No. CT 2016-0003, before the Puerto Rico Supreme Court, 2016 TSPR 38. Defended the Governor’s authority to appoint the Chief Justice of the Puerto Rico Supreme Court.

González-Oyarzún v. Caribbean City Builders et al, Appeal Nos. 14-1954 & 14-197, before the U.S. Court of Appeals for the First Circuit, 798 F.3d 26 (1st Cir. 2015). Successfully advocated that the 7th Amendment right to jury trial in civil proceedings does not apply to Puerto Rico.

Doral Financial Corp. et al v. Estado Libre Asociado de Puerto Rico, before the Puerto Rico Court of Appeals, KLAN 2014-2094; KLAN 2014- 2102; KLCE 2014-1729. Successfully argued that a Closing Agreement upon which Doral Bank requested a tax refund of approximately 230 million dollars, was null and void.

Oficina de Asuntos Monopolísticos v. Jiménez Galarza et als, Consolidated Appeals, CC-2015-988; CC-2015-107; CC-2016-0037; AC-2016-0099; CC-206-0107; CC-1026-0343; CC-2016-0366, argued on December 6, 2016, before the Puerto Rico Supreme Court. Antitrust matter regarding applicability of the Commonwealth’s Antitrust statute to public service corporations licensed by the Commonwealth’s Public Service Commission.

BBVA et al v. Commonwealth of Puerto Rico, Case No. CC 2012-0767 and CC 2013-1077, argued on March 1, 2016. Before the Puerto Rico Supreme Court. Involved applicability of res judicata and collateral estoppel principles to civil in rem forfeiture proceeding. Defended the constitutionality of the Commonwealth’s civil forfeiture statute of 2011.

Puerto Rico Teacher’s Association v. Teacher’s Retirement Fund et al, Case No. CT 2014-0002, argued on March 26, 2014, 190 DPR 854 (2014), before the Puerto Rico Supreme Court. Defended the constitutionality and retroactive application of the Teacher’s Pension Reform Act of 2013.

Watchtower Bible and Tract Society of New York Inc. et al v. Municipality of Dorado, Case No. CT 2013­0014, argued on February 11, 2014, 192 DPR 73 (2014), before the Puerto Rico Supreme Court. Argued as amicus, that residential roads in Puerto Rico are part of the public domain.

Brau Linares v. Commonwealth of Puerto Rico, Case No. CT 2013-00021, argued on January 15, 2014, 190 DPR 315 (2014), before the Puerto Rico Supreme Court. Defended the constitutionality and retroactive application of the Judiciary Pension Reform Act of 2013.

Autonomous Municipality of San Germán v. QMC Telecom et al, Case No. CC 2012-0233, argued on May 7, 2013, 190 DPR 652 (2014), before the Puerto Rico Supreme Court. Defended administrative decision to allow installation of a telecommunications transmitter.

Massó-Torrellas et al v. Municipality of Toa Alta et al., Appeal No. 16-1319, argued November 4, 2016, before the U.S. Court of Appeals for the First Circuit. Case involving enforcement of forum selection clause and Constitutional claims under the First, Fourth and Fourteenth Amendments to the Constitution of the United States.

Wal-Mart Puerto Rico v. Zaragoza-Gómez et al, Appeal Nos. 16-1370; 16-1406, argued on June 6, 2017, __ F.3d __ (August 24, 2016), before the U.S. Court of Appeals for the First Circuit. Argued that the Court lacked subject-matter jurisdiction under the Butler and Tax Injunction Acts. Defended the constitutionality of the Commonwealth of Puerto Rico’s Alternative Minimum Tax.