The underlying theory and internal coherence of separation of powers is examined. It is noted that the classic rationale for the separation of power is to prevent tyranny by placing execution of the laws in hands independent from those of the legislature. The author summarizes various opinions that contradict this rationale. For example, Synar stated that the legislature and the Executive were directly accountable to the people if they neglected interbranch checks between them. The separation of powers theory, which justifies the claimed enforcement prerogative, is examined from a constitutional perspective. The author also reports on the consequences of federalism. One of these consequences is that there is no general Federal police power. The theory of separation of powers is also examined to ascertain if the theory coheres with present law enforcement. Federal law enforcement and Federal prosecutorial jurisdiction are outlined. Various constitutional provisions regarding the separation of powers are reviewed, and the author concludes that the bulk of modern government is executive in nature. 548 references.