Your comment reflects a common, but fundamentally mistaken, understanding of the constitution. You're thinking of the government like an operating system with a microkernel that is trusted to neutrally enforce the "law," with the three branches of government running in userspace.
That's not the system the founders created! They understood that everyone is political, and no one can be trusted. The founders understood the "who watches the watchers" problem and created a system without any such single point of failure. The ultimate backstop in our political system is not the law, but instead frequent elections. Congress writes the law, the President enforces the law, and the Judiciary interprets the law. If the President does a bad job of enforcing the law, the recourse is elections (or, as a last resort, impeachment).