Fact Sheet on Legal Authorities for Isolation/Quarantine

Printer friendly version [2 pages]


  • Isolation and quarantine are two common public health strategies designed to protect the public by preventing exposure to infected or potentially infected persons.
  • In general, isolation refers to the separation of persons who have a specific infectious illness from those who are healthy and the restriction of their movement to stop the spread of that illness. Isolation is a standard procedure used in hospitals today for patients with tuberculosis and certain other infectious diseases.
  • Quarantine, in contrast, generally refers to the separation and restriction of movement of persons who, while not yet ill, have been exposed to an infectious agent and therefore may become infectious. Quarantine of exposed persons is a public health strategy, like isolation, that is intended to stop the spread of infectious disease.
  • Both isolation and quarantine may be conducted on a voluntary basis or compelled on a mandatory basis through legal authority.

State and Local Law

  • A state’s authority to compel isolation and quarantine within its borders is derived from its inherent “police power” — the authority of a state government to enact laws and promote regulations to safeguard the health, safety, and welfare of its citizens. As a result of this authority, the individual states are responsible for intrastate isolation and quarantine practices, and they conduct their activities in accordance with their respective statutes.
  • State and local laws and regulations regarding the issues of compelled isolation and quarantine vary widely. Historically, some states have codified extensive procedural provisions related to the enforcement of these public health measures, whereas other states rely on older statutory provisions that can be very broad. In some jurisdictions, local health departments are governed by the provisions of state law; in other settings, local health authorities may be responsible for enforcing state or more stringent local measures. In many states, violation of a quarantine order constitutes a criminal misdemeanor.
  • Examples of other public health actions that can be compelled by legal authorities include disease reporting, immunization for school attendance, and tuberculosis treatment.

 Top of Page

Federal Law

  • The HHS Secretary has statutory responsibility for preventing the introduction, transmission, and spread of communicable diseases from foreign countries into the United States , e.g., at international ports of arrival, and from one state or possession into another.
  • The communicable diseases for which federal isolation and quarantine are authorized are set forth through executive order of the President and include: cholera, diphtheria, infectious tuberculosis, plague, smallpox, yellow fever, and viral hemorrhagic fevers . Severe acute respiratory syndrome (SARS) was added to this list in April 2003.
  • By statute, U.S. Customs and Coast Guard officers are required to aid in the enforcement of quarantine rules and regulations. Violation of federal quarantine rules and regulations constitutes a criminal misdemeanor, punishable by fine and/or imprisonment.
  • Federal quarantine authority includes the authority to release persons from quarantine on the condition that they comply with medical monitoring and surveillance.

Interplay between Federal and State/Local Laws

  • States and local jurisdictions have primary responsibility for isolation and quarantine within their borders. The federal government has residual authority under the Commerce Clause of the U.S. Constitution to prevent the interstate spread of disease.
  • The federal government has primary responsibility for preventing the introduction of communicable diseases from foreign countries into the United States .
  • By statute, the HHS Secretary may accept state and local assistance in the enforcement of federal quarantine regulations and may assist states and local officials in the control of communicable diseases.
  • It is possible for federal, state, and local health authorities simultaneously to have separate but concurrent legal quarantine power in a particular situation (e.g., an arriving aircraft at a large city airport).
  • Because isolation and quarantine are “police power” functions, public health officials at the federal, state, and local levels may occasionally seek the assistance of their respective law enforcement counterparts to enforce a public health order.

 Top of Page

View Page In: PDF [244K]