The Chief of Mission and DCM Authority
How U.S. Chiefs of Mission and their Deputies exercise statutory authority over embassy operations, country teams, and interagency staffing under 22 U.S.C. § 3927 and NSDD-38.
The Statutory and Presidential Basis of COM Authority
The Chief of Mission (COM) is the senior U.S. government representative in a foreign country and the personal representative of the President. The authority is grounded in two instruments: Section 207 of the Foreign Service Act of 1980 (22 U.S.C. § 3927) and the President's Letter of Instruction issued at the outset of each ambassadorship. Section 207 vests the COM with "full responsibility for the direction, coordination, and supervision of all Government executive branch employees in that country," with the sole carve-out of personnel under the command of a U.S. area military commander or on the staff of an international organization.
The Letter of Instruction, reissued by every President since John F. Kennedy's May 29, 1961 letter to ambassadors, makes the chain of command explicit: the COM reports to the President through the Secretary of State. The most recent iteration, signed by President Biden in 2022 and continued in form by subsequent administrations, reaffirms that all executive branch personnel — including those of the Department of Defense, intelligence community, Department of Commerce, USAID, and Department of Agriculture — operate under COM authority. The CIA Chief of Station, FBI Legal Attaché, and Defense Attaché all serve at the COM's direction in-country, regardless of their separate reporting chains in Washington.
Scope, Limits, and the NSDD-38 Mechanism
COM authority is geographic, not functional. It extends to every U.S. government civilian and uniformed employee physically present in the country of accreditation, including those on temporary duty (TDY). The COM must concur — or refuse concurrence — before any U.S. agency may establish, expand, or modify its staffing footprint at post. This is the National Security Decision Directive 38 process, signed by President Reagan on June 2, 1982, which remains the controlling interagency mechanism. An agency seeking to add a position files an NSDD-38 request through the Department of State's Bureau of Management; the COM's decision is final, appealable only to the President.
The limits are narrow but important. Forces under the operational command of a geographic combatant commander (CENTCOM, AFRICOM, INDOPACOM, etc.) fall outside Section 207, though the COM retains coordination authority and Title 22 responsibility for their presence. The 1997 "dual-hatted" arrangement codified in the Goldwater-Nichols implementation guidance requires the combatant commander and COM to maintain written agreement on the demarcation. Multilateral mission staff — UN, NATO, OSCE personnel — are likewise outside COM control, though the COM remains the senior bilateral interlocutor.
Ambassadors confirmed under Article II, Section 2 of the Constitution hold the rank of Ambassador Extraordinary and Plenipotentiary. In the absence of a confirmed ambassador, the Chargé d'Affaires ad interim exercises identical COM authority. The 2014 vacancy in Moscow following Ambassador McFaul's departure and the 2017-2019 vacancy in Riyadh illustrate how Chargé tenures of a year or more are not unusual; the Chargé's authority is undiminished.
The COM's exercise of authority is not symbolic. In 2010, Ambassador Karl Eikenberry's classified cables from Kabul questioning the troop surge — leaked later — demonstrated the COM's prerogative to challenge military assessments directly to Washington. In 2012, Ambassador Robert Ford's recall from Damascus and continued accreditation from outside Syria showed that COM functions can persist even without physical presence, until formal closure of the mission.