Now that I’m interested in this question, I’m probing to see where the idea that the three branches are equal comes from. As far as I can tell, the first reference to that idea comes in President Andrew Jackson’s 1834 Protest to the Censure Resolution, which I spent a good deal of time discussing in my first book. In making the case for executive power, Jackson asserted that each of the three branches “is the co-equal of the other two.” (Congress, of course, argued at the time that this was not the case.)
The first clear reference to co-equal branches by the Supreme Court is in Field v. Clark, an 1892 case holding that the Court must defer to Congress’s assertion that a law was duly enacted (in other words, the Court will not look behind the existence of an enrolled bill). In that case, the Court stated: “The respect due to coequal and independent departments requires the judicial department to act upon that assurance, and to accept, as having passed congress, all bills authenticated in the manner stated; leaving the courts to determine, when the question properly arises, whether the act so authenticated, is in conformity with the constitution.” The result in Field, though, is just as consistent with a claim of congressional superiority. There is also language from some taxpayer standing cases (until Flast v. Cohen), saying there is no such standing and thus the Court cannot review appropriations by a “co-equal” branch, but again co-equal does no work for that analysis.
From what I see, the idea that there are three co-equal branches really did not take hold until Watergate. The Court mentions the point in United States v. Nixon, and President Ford made the same observation in his speech to Congress immediately following Nixon’s resignation. At this point, though, coequality was a device to limit the Executive Branch rather than enhance it.
Why does this matter? I’ll tell you next week.