As best I can tell, the short answer to your question, Ryan, is that the founders did not even consider election of judges at the time they drafted the Constitution. In the Federalist Papers, No. 76, Alexander Hamilton wrote that
It will be agreed on all hands that the power of appointment, in ordinary cases can be properly modified only in one of three ways. If ought either to be vested in a single man, or in a select assembly of a moderate number, or in a single man with the concurrence of such an assembly.Of course, as you point out, all hands would no longer agree those are the only options for selecting judges that are on the table. To be sure, other methods of selection might more properly be referred to as something other than "appointment." Two other models have been implemented in the United States: election and merit selection. (For more background on these other methods, see these materials posted in connection with Frontline's special titled, "Justice For Sale.") To avoid this post becoming too unmanageable, I will focus upon the election of judges -- in particular, the election of appellate judges.
The election of trial or magistrate judges has a very long history -- too long to trace its source by this amateur historian. According to this article (again from materials provided by Frontline), Mississippi was the first state to require the election of all judges (in 1832). Many states followed course, particularly in the period between 1846 and 1860, during which period many states revamped their state constitutions. According to this press release by the Brennan Center for Justice at the NYU School of Law, as of 2002 38 states, representing 87% of all state judges, use elections to select judges. In 18 of these 38 states, judges are initially selected by election; in the remainder judges are appointed and then must be reelected to stay in office.
There is too sizable a debate to summarize here all the reasons in support of and against each methods of selecting judges. The argument I would make against the election of judges conforms with the reasons Hamilton offered in No. 78 of the Federalist Papers, but a brief lead-in is first necessary. I assume the election of judges entails not only the initial selection of judges, but also their periodic reelection -- as far as I can ascertain, no state has ever instituted a system by which judges are initially selected and remain in office "during good behavior," the standard the Constitution provides for Article III judges.
In my view, the harm of electing judges comes about by subjecting the interpretation and application of the law to the same public pressure as is responsible for crafting of the law. Assume a narrow majority succeeds in promulgating some vague standard of behavior to which all citizens must comply -- insert any controversial issue of your choice, particularly those involving criminal behavior or health and safety standards (euthanasia, abortion, and the prohibition of recreational drugs come to mind). Assume also that a harsher standard could not have garnered a majority. It is reasonable to expect, and experience confirms, that judges will often favor the harshest reading of the law that can be reasonably extracted from the text (and sometimes even unreasonable interpretations too) out of concern for getting reelected. The concern, to frame it differently, is that judicial interpretation plays less in most electors' minds than does outcome -- a tendency I suspect often factors into the decisions of elected judges. That concern is more significant where the law to be interpreted is a constitution, which serves in part to protect the rights of the minority.
My argument against election of judges, therefore, depends more upon the value of the life tenure of judges than it does upon how they are initially selected. I entirely agree with the sentiments expressed by Hamilton when he stated that
The standard of good behavior for the continuance in office of the judicial magistracy is certainly one of the most valuable improvements in the practice of government. In a monarchy it is an excellent barrier to the despotism of the prince; in a republic it is no a less excellent barrier to the encroachments and oppressions of the representative body. And it is the best expedient which can be devised in any government to secure a steady, upright, and impartial administration of the laws.Here (in RealMedia format) is a video excerpt of an interview with Justices Kennedy and Breyer displaying some hostility to the concept of election of judges.
I would be happy to elaborate upon any points I made here or, for that matter, upon points I missed. More important, I would be very happy to learn what you think.