Dukes County, Massachusetts: Government, Services, and Structure

Dukes County occupies the western islands of Massachusetts, encompassing Martha's Vineyard and the Elizabeth Islands, and functions as one of the Commonwealth's 14 counties under a structure governed by Massachusetts General Laws. The county's governmental organization is distinct from most Massachusetts counties due to the near-total absence of traditional county-level administrative functions and the dominant role played by six independent towns. This page describes the county's jurisdictional boundaries, governmental structure, service delivery mechanisms, and the statutory framework that defines what Dukes County government can and cannot do.

Definition and scope

Dukes County is a Massachusetts county government established under Massachusetts General Laws Chapter 34, which governs county organization statewide. Its territorial jurisdiction covers Martha's Vineyard — comprising the six incorporated towns of Aquinnah, Chilmark, Edgartown, Oak Bluffs, Tisbury, and West Tisbury — along with the Elizabeth Islands, which are administratively part of the town of Gosnold. The permanent population of the island chain, recorded at approximately 17,352 residents in the 2020 U.S. Census, swells significantly during summer months due to tourism.

Unlike most Massachusetts counties, Dukes County retains a functioning county commission — a 3-member elected Board of County Commissioners — that exercises limited administrative authority. County government does not provide municipal services directly; those functions fall entirely to the six constituent towns under the Massachusetts municipal home rule framework. The county does maintain a registry of deeds and a sheriff's office, both of which are statutory county functions preserved across Massachusetts.

The scope of this reference covers Dukes County's governmental structure and publicly administered services. It does not address private or nonprofit service providers, federal programs administered without state or county intermediation, or the internal governance of individual towns within the county. Tribal governance of the Wampanoag Tribe of Gay Head (Aquinnah), a federally recognized nation, falls outside the scope of county or state civil authority on tribal lands. For the broader Massachusetts county landscape, the /index provides an orientation to all 14 counties and statewide governmental reference points.

How it works

Dukes County government operates through three structural pillars: the Board of County Commissioners, the elected Sheriff, and the Register of Deeds.

  1. Board of County Commissioners: Three commissioners are elected at-large to 4-year staggered terms. The board holds authority over the county budget, county-owned properties, and intergovernmental coordination. The county budget is modest compared with mainland counties; as of fiscal year 2023, the county operating budget was funded primarily through county assessments levied against the six towns proportionally (Dukes County Commission, FY2023 Budget).
  2. Sheriff's Office: The Dukes County Sheriff is elected to a 6-year term under M.G.L. Chapter 37. The Sheriff's Office provides civil process service, manages the county house of correction, and provides transportation services for court-involved individuals.
  3. Registry of Deeds: The Dukes County Registry of Deeds records land title instruments — deeds, mortgages, liens, and easements — for all real property within the county's geographic jurisdiction. This function is exercised under M.G.L. Chapter 36.

The county does not operate a courthouse independent of the Massachusetts Trial Court system. District and Superior Court sessions for Dukes County are held at the Edgartown courthouse, which falls under the administrative authority of the Massachusetts Supreme Judicial Court through the Trial Court's Southeastern Division.

The county has no county-level police department, no county public health department, and no county school district. Education governance rests entirely with individual Massachusetts school districts at the town level.

Common scenarios

The following scenarios represent the most frequent intersections between residents, property owners, or professionals and Dukes County governmental functions:

Decision boundaries

Dukes County vs. individual towns: County government does not supersede town government for zoning, permitting, local road maintenance, public safety, or social services. Those functions rest exclusively with the selectboards and town administrators of each constituent town under Massachusetts select board authority. Disputes over land use, bylaws, or municipal services must be directed to the relevant town government, not the county commission.

Dukes County vs. the Commonwealth: State agencies — including the Massachusetts Department of Public Health, the Massachusetts Department of Environmental Protection, and the Massachusetts Department of Transportation — retain direct jurisdiction over state-regulated activities within the county. County commissioners have no authority to waive or modify state regulatory requirements.

Dukes County vs. federal jurisdiction: The Wampanoag Tribe of Gay Head (Aquinnah) holds a federal trust land designation for a portion of Aquinnah. On those lands, tribal law and federal Indian law govern; Massachusetts civil and criminal jurisdiction is limited by federal statute (25 U.S.C. § 1721 et seq., the Gay Head (Aquinnah) Indian Claims Settlement Act).

Dukes County vs. Nantucket County: Nantucket County presents the most direct structural comparison to Dukes County. Both are island counties with small permanent populations and limited county-level administrative capacity. However, Nantucket County and Nantucket town are coterminous — a single governmental entity — whereas Dukes County contains 6 legally independent towns. This distinction produces fundamentally different administrative relationships between county and municipal government in the two jurisdictions.

References