Final answer:
The doctrine from 6 Comp.Gen 619 (1927) is the doctrine of implied powers, supporting Congress's ability to enact laws that are necessary and proper. This doctrine works alongside the national supremacy principle, which establishes federal law as supreme over state law.
Step-by-step explanation:
The doctrine defined by the clause presented in 6 Comp.Gen 619 (1927) is the doctrine of implied powers and the principle of national supremacy. This doctrine permits Congress to enact laws necessary and proper to execute its constitutional powers, even if not explicitly stated in the Constitution. Moreover, the principle of national supremacy, established by the Supremacy Clause in Article VI of the Constitution, asserts that federal laws and the Constitution take precedence over any conflicting state laws.
The Supremacy Clause has been a cornerstone of constitutional law, ensuring that the federal government operates with authority over states in matters within its jurisdiction. The inclusion of the necessary and proper clause in Article I of the Constitution further reinforces the federal government's ability to legislate effectively within its constitutional authority.