Executive Branch

To simplify, the role of the executive branch in the system of checks-and-balances is not emphasized in the discussion.   However, if the Federal courts were intended to be the last line of defense against an unconstitutional Congress, the authors of the Constitution intended the office of the President to be the first line.  This is substantiated by the Second Article, where the presidential oath is specified as follows.  "I do solemnly swear (or affirm) that I will faithfully execute the office of President of the United States, and will to the best of my ability, preserve, protect and defend the Constitution of the United States."

In the earlier years of the Nation, the president’s inclination to sign or veto legislation was indeed dependent on his assessment of its constitutionality.   Many of the bills that were handed back to Congress for reconsideration were for that reason.  Over time, as the Nation’s political culture evolved into a system of two major parties, the executive branch’s discipline for such things has progressively waned.  Now days, congressional legislation is more likely signed or vetoed solely on whether it is consistent with the President’s own political agenda.   For all practical purposes the only time the executive branch questions the constitutionality of a bill is when the bill doesn’t suit that agenda.  This corruption in the system of checks and balances, makes it all the more imperative that the Federal courts retain the power to hold the line against both Congress and the Presidency.