No agency of the federal government would administer marriage laws, since marriage has always been a state issue in this country. When the US Supreme Court struck down section 3 of the Defense of Marriage Act on June 26, 2013, the federal agencies most affected were: (1) the Internal Revenue Service; (2) the Social Security Administration; (3) the Bureau of Citizenship and Immigration Services; (4) all five branches of the US Armed Forces.
The responsibility for administering same-sex marriage legislation lies primarily with the individual states, as the regulation and recognition of marriage falls under state jurisdiction. The federal government's role is limited to ensuring equal protection and benefits for same-sex couples, which is primarily overseen by the Department of Justice, specifically the Civil Rights Division.
The Executive Department thru the Department of Education
Judiciary is a noun. It refers to the branch of government responsible for interpreting laws and administering justice.
WAr it was the department of war
Global Affairs Canada is the Canadian government department responsible for foreign affairs.
The department of defense
executive
Usually, the government of the country is responsible for declaring war. In the United States of America, the Department of Defense is responsible for declaring wars.
In most countries, the judiciary is separate from the executive and legislative branches of government to ensure its independence. The judiciary is typically overseen by a Ministry of Justice or similar department, but judges and courts operate independently in their decision-making.
Department of the Treasury
the department of health and human serveries
Centers for Medicaid and Medicare Services
Here in the Philippines, the Department of Environment and Natural Resoures is responsible for the environment.