Sean M. Grammel

Partner

Overview

Sean’s significant experience at both the trial and appellate levels allows him to guide clients, from municipalities to private parties, through complex disputes involving government action, property rights, and regulatory frameworks.

Sean serves as special counsel to municipalities, government agencies, and public officials in high-stakes disputes, investigations, and compliance matters. His practice focuses on defending public entities and officials in complex litigation, including claims brought under the Massachusetts Civil Rights Act (MCRA), tort claims, land use and zoning disputes, and matters involving governmental authority and immunity.

Sean also has significant experience representing municipalities and public sector clients in property and land use disputes, including conflicts involving zoning, regulatory takings, and development rights. He advises and litigates matters involving railroads, airports, and transportation infrastructure, including disputes governed by federal preemption.

In addition to his public sector work, Sean represents clients in high-value commercial and regulatory disputes, internal investigations, and appellate litigation. He regularly develops and executes strategic defenses for clients facing urgent legal challenges, including injunctions, enforcement actions, and constitutional claims.

Sean has spent years counseling clients on litigation risks and advocating for them at the trial and appellate levels.  This wealth of experience helps Sean develop and then execute an efficient strategy to achieve his clients’ goals.

BEYOND THE OFFICE

Sean lives with his partner and three kids in Mansfield.  He likes to spend his time outside of work like a typical dad: browsing for good nonfiction at the library, taking care of his many plants, or trying out new recipes for dinner.

PRACTICE AREAS

Credentials

Education

University of Pennsylvania Law School, J.D., 2013, magna cum laude
Senior Editor, University of Pennsylvania Law Review

University of Notre Dame, B.A., 2010, magna cum laude

Admissions

Massachusetts

U.S. District Court, District of Massachusetts

U.S. District Court, Eastern District of Michigan

Court of International Trade

United States Court of Appeals for the First Circuit

United States Court of Appeals for the Second Circuit

United States Court of Appeals for the Eighth Circuit

United States Court of Appeals for the D.C. Circuit

Certifications

Certified Member of the Appellate Panel for the Children and Family Law Division of the Committee for Public Counsel Services

 

Languages

Spanish

Recognition

Massachusetts Super Lawyers, Rising Star, 2026

Affiliations

Massachusetts LGBTQ Bar Association

Boston Bar Association

Massachusetts Bar Association

Association of Transportation Law Professionals

 

Experience

Sean’s experience includes:

Special Counsel to Municipalities, Government Agencies, and Public Officials

Represents public sector clients as special counsel in civil rights, regulatory, and high-stakes litigation

  • Serves as special litigation counsel to municipalities and government entities in high-stakes disputes involving property rights, infrastructure, and regulatory authority
  • Defends municipalities and public officials against claims under the Massachusetts Civil Rights Act (MCRA) and related constitutional and tort claims, including routinely obtaining dismissals at the Rule 12 stage
  • Secured appellate decision affirming common law immunity for municipal officials against intentional tort and MCRA claims
  • Represented state agency in defeating a multi-million dollar regulatory takings claim
  • Defended municipalities against multiple requests for preliminary injunctions, including challenges to COVID-related public health measures, and successfully handled related appeals
  • Advised municipalities on labor and governance issues, including negotiations with public employee committees
  • Represented former state official in response to subpoenas in multiple matters involving government investigations

Railroad, Transportation, and Preemption Disputes

Handles disputes involving railroads, airports, and federally regulated infrastructure

  • Acts as special counsel in property disputes with railroads, including matters involving federal preemption under the Interstate Commerce Commission Termination Act (ICCTA)
  • Appeared before the Surface Transportation Board in multiple matters involving railroad operations and ICCTA preemption of state and local property rights
  • Represents municipalities and airport commissions in disputes involving airport land use, tenant conflicts, and access rights
  • Obtained dismissals for airports in disputes involving federal constitutional, statutory, and regulatory claims related to airport operations
  • Filed appellate amicus briefs addressing federal preemption, airport access, and transportation regulatory frameworks
  • Advised airports on use, leasing, and disposition of airport property, including non-aeronautical uses, First Amendment requirements, and regulatory compliance

Land Use, Zoning, and Property Disputes

Represents municipalities, developers, and property owners in zoning, land use, and property rights litigation

  • Represents municipalities, developers, and private parties in land use and zoning disputes, including permitting, development rights, and enforcement actions
  • Litigates property disputes involving zoning restrictions, trespass, and interference with property rights
  • Represents clients in disputes involving federal and state civil rights claims, including the Massachusetts Civil Rights Act (MCRA), arising from land use decisions
  • Litigates property disputes involving the application or enforcement of rights under Chapter 61, Chapter 61A, and Chapter 61B
  • Successfully defended municipality in zoning dispute allowing construction of a public safety building to proceed as permitted
  • Handles disputes involving contractors, engineers, and development projects, including claims for negligent design and delay damages

High-Stakes Commercial and Regulatory Litigation

Handles complex commercial disputes and regulatory litigation involving significant financial and operational risk

  • Represents clients in complex commercial litigation and regulatory disputes, including claims under Chapters 93A and 176D
  • Won arbitration involving rights to commercialize a product with projected $1 billion annual revenue
  • Successfully defended biotechnology company in federal jury trial involving $138 million in contract and fraud claims
  • Obtained summary judgment in multiple courts in product liability and regulatory cases
  • Resolved federal civil rights claims against national retailer efficiently prior to incurring significant litigation costs

Government and Internal Investigations

Conducts internal investigations and advises public sector clients on compliance, risk, and potential enforcement exposure.

  • Conducts, and advises on, internal investigations for state and municipal entities, including allegations of misconduct and regulatory violations
  • Worked with federal prosecutors in connection with potential criminal investigations involving employees at state agency
  • Investigated municipal election operations and advised on compliance and procedural reforms
  • Investigated allegations of misconduct by senior official at state agency and advised client on risk mitigation and litigation exposure arising from internal findings

Public Interest Work

Sean has significant public interest experience, including years spent on his feet in the courtroom as a public defender.  While at A&K, he has briefed, argued, and won multiple children’s welfare appeals in the Massachusetts Appeals Court.  He also worked with other A&K attorneys to negotiate a settlement with the federal government to implement the import provisions of the Marine Mammal Protection Act.  Sean has contributed to numerous other pro bono matters at A&K and is a member of the firm’s Pro Bono Committee.

Sean’s significant experience at both the trial and appellate levels allows him to guide clients, from municipalities to private parties, through complex disputes involving government action, property rights, and regulatory frameworks.

Sean serves as special counsel to municipalities, government agencies, and public officials in high-stakes disputes, investigations, and compliance matters. His practice focuses on defending public entities and officials in complex litigation, including claims brought under the Massachusetts Civil Rights Act (MCRA), tort claims, land use and zoning disputes, and matters involving governmental authority and immunity.

Sean also has significant experience representing municipalities and public sector clients in property and land use disputes, including conflicts involving zoning, regulatory takings, and development rights. He advises and litigates matters involving railroads, airports, and transportation infrastructure, including disputes governed by federal preemption.

In addition to his public sector work, Sean represents clients in high-value commercial and regulatory disputes, internal investigations, and appellate litigation. He regularly develops and executes strategic defenses for clients facing urgent legal challenges, including injunctions, enforcement actions, and constitutional claims.

Sean has spent years counseling clients on litigation risks and advocating for them at the trial and appellate levels.  This wealth of experience helps Sean develop and then execute an efficient strategy to achieve his clients’ goals.

BEYOND THE OFFICE

Sean lives with his partner and three kids in Mansfield.  He likes to spend his time outside of work like a typical dad: browsing for good nonfiction at the library, taking care of his many plants, or trying out new recipes for dinner.

Education

University of Pennsylvania Law School, J.D., 2013, magna cum laude
Senior Editor, University of Pennsylvania Law Review

University of Notre Dame, B.A., 2010, magna cum laude

Admissions

Massachusetts

U.S. District Court, District of Massachusetts

U.S. District Court, Eastern District of Michigan

Court of International Trade

United States Court of Appeals for the First Circuit

United States Court of Appeals for the Second Circuit

United States Court of Appeals for the Eighth Circuit

United States Court of Appeals for the D.C. Circuit

Admissions

Certified Member of the Appellate Panel for the Children and Family Law Division of the Committee for Public Counsel Services

 

Languages

Spanish

Massachusetts Super Lawyers, Rising Star, 2026

Massachusetts LGBTQ Bar Association

Boston Bar Association

Massachusetts Bar Association

Association of Transportation Law Professionals

 

Sean’s experience includes:

Special Counsel to Municipalities, Government Agencies, and Public Officials

Represents public sector clients as special counsel in civil rights, regulatory, and high-stakes litigation

  • Serves as special litigation counsel to municipalities and government entities in high-stakes disputes involving property rights, infrastructure, and regulatory authority
  • Defends municipalities and public officials against claims under the Massachusetts Civil Rights Act (MCRA) and related constitutional and tort claims, including routinely obtaining dismissals at the Rule 12 stage
  • Secured appellate decision affirming common law immunity for municipal officials against intentional tort and MCRA claims
  • Represented state agency in defeating a multi-million dollar regulatory takings claim
  • Defended municipalities against multiple requests for preliminary injunctions, including challenges to COVID-related public health measures, and successfully handled related appeals
  • Advised municipalities on labor and governance issues, including negotiations with public employee committees
  • Represented former state official in response to subpoenas in multiple matters involving government investigations

Railroad, Transportation, and Preemption Disputes

Handles disputes involving railroads, airports, and federally regulated infrastructure

  • Acts as special counsel in property disputes with railroads, including matters involving federal preemption under the Interstate Commerce Commission Termination Act (ICCTA)
  • Appeared before the Surface Transportation Board in multiple matters involving railroad operations and ICCTA preemption of state and local property rights
  • Represents municipalities and airport commissions in disputes involving airport land use, tenant conflicts, and access rights
  • Obtained dismissals for airports in disputes involving federal constitutional, statutory, and regulatory claims related to airport operations
  • Filed appellate amicus briefs addressing federal preemption, airport access, and transportation regulatory frameworks
  • Advised airports on use, leasing, and disposition of airport property, including non-aeronautical uses, First Amendment requirements, and regulatory compliance

Land Use, Zoning, and Property Disputes

Represents municipalities, developers, and property owners in zoning, land use, and property rights litigation

  • Represents municipalities, developers, and private parties in land use and zoning disputes, including permitting, development rights, and enforcement actions
  • Litigates property disputes involving zoning restrictions, trespass, and interference with property rights
  • Represents clients in disputes involving federal and state civil rights claims, including the Massachusetts Civil Rights Act (MCRA), arising from land use decisions
  • Litigates property disputes involving the application or enforcement of rights under Chapter 61, Chapter 61A, and Chapter 61B
  • Successfully defended municipality in zoning dispute allowing construction of a public safety building to proceed as permitted
  • Handles disputes involving contractors, engineers, and development projects, including claims for negligent design and delay damages

High-Stakes Commercial and Regulatory Litigation

Handles complex commercial disputes and regulatory litigation involving significant financial and operational risk

  • Represents clients in complex commercial litigation and regulatory disputes, including claims under Chapters 93A and 176D
  • Won arbitration involving rights to commercialize a product with projected $1 billion annual revenue
  • Successfully defended biotechnology company in federal jury trial involving $138 million in contract and fraud claims
  • Obtained summary judgment in multiple courts in product liability and regulatory cases
  • Resolved federal civil rights claims against national retailer efficiently prior to incurring significant litigation costs

Government and Internal Investigations

Conducts internal investigations and advises public sector clients on compliance, risk, and potential enforcement exposure.

  • Conducts, and advises on, internal investigations for state and municipal entities, including allegations of misconduct and regulatory violations
  • Worked with federal prosecutors in connection with potential criminal investigations involving employees at state agency
  • Investigated municipal election operations and advised on compliance and procedural reforms
  • Investigated allegations of misconduct by senior official at state agency and advised client on risk mitigation and litigation exposure arising from internal findings

Public Interest Work

Sean has significant public interest experience, including years spent on his feet in the courtroom as a public defender.  While at A&K, he has briefed, argued, and won multiple children’s welfare appeals in the Massachusetts Appeals Court.  He also worked with other A&K attorneys to negotiate a settlement with the federal government to implement the import provisions of the Marine Mammal Protection Act.  Sean has contributed to numerous other pro bono matters at A&K and is a member of the firm’s Pro Bono Committee.