The Constitution provides critical guidance on how to strike the balance between ordinary and specialized legal meanings of its terms: It calls for most important legal issues to be adjudicated in jury trials, with juries selected more or less at random from the general community, which hopefully results in a panel of twelve mostly reasonable persons, or who become more reasonable when thus empaneled. But the original meaning of "jury trial" was that all legal issues be made to the jury, not just to the judge, so that in reaching a verdict, the jury is also reviewing the legal argument and the decisions on points of law made by the judge. Many trials will involve subtle legal issues with which the jurors will not be familiar at the outset, but for which they hopefully will become sufficiently knowledgeable by the time they are asked to render a verdict. That essentially defines a standard of interpretation that is accessible to ordinary people during the intense legal education that is a trial, but not necessarily known to them before that process begins.
There is also guidance from the way the Constitution was ratified: By conventions in each state, elected by the people, but composed of a high proportion of lawyers, who also dominated the debates.
Finally, we see the process during the Philadelphia Convention, when members unsure of the meaning of some of the proposed language (such as "ex post facto") referred to Blackstone or other legal authorities to settle the question. That is a microcosm of how they expected other constitutional terms to be resolved.
The people who elected the ratifiers mostly did not do so on the basis of subtle understanding of the Constitution. They seldom if ever even debated most of the issues we consider important for deciding cases today. Some had a general support (based on the expectation Washington would be the first president), or opposition (fear of change), but mostly because they liked and trusted the ratifiers as personalities.
And these three points are not about a single resolution, but insights into a more general interpretative regime the Framers and Ratifiers expected to play out, sometimes pulling in one direction, sometimes in another. There is not an algorithm to be found.
But they did expect the Constitution to be interpreted by legal elites, as they expected legal issues generally to be. That's what they had courts and lawyers for. But those courts were open to lay interpretation in one important way: the jury. However, while legal issues were originally supposed to be argued in the presence of the jury (unlike the practice today), the jury, along with the judge and opposing lawyers, expected the trial process to be an intense exploration of the laws involved, in which all participants learned to understand the legal issues, and when in doubt about what legal terms meant, to consult legal authorities. As independent-minded as they might be, respect for expert authority was the prevailing paradigm, and one they not only expected would continue, and could not conceive of doing things otherwise, but comprised an essential part of the meanings of the terms used, not only in the Constitution, but in law generally.
Yes, one of the "populists" was Chief Justice John Marshall, largely self-taught in the law and ignorant of legal history, when he invoked lay meaning of the term "necessary" as "convenient" in McCulloch v. Maryland. Jefferson and Madison didn't agree, and I am disposed to go with their Whig approach to interpretation, as distinct from Tory ("Mansfieldism"), or Monarchist. There were those three schools of common law interpretation, and at the Founding, the prevailing one was Whig, at least during the Jeffersonian Era.
Proper interpretation (or construction) is not a matter of following a rule to be found, but a complex process constrained by structures, procedures, and common law rules of interpretation, represented in part by the legal maxims.
After many decades of research, I have reached the point where I can quickly resolve almost any constitutional question in a way that seems congruent with the thinking of the Founders, to the extent that can be discerned. But if graphed it would look like an extremely complicated flow chart, that even includes some nondeterministic decision nodes. Imparting that to others, however, is a challenge.
The alternatives are misframed by use of the terms "elitist" and "populist", which are distinctly modern terms, not 18th century terms. The proper distinction is between (legally) "learned" and "unlearned", and that is the way even lay persons would have distinguished the two approaches. We find no significant evidence that any laypersons in the founding era insisted on "unlearned" use of what are legal terms because they are used in a law, which makes them legal terms by definition. The average man in the street in 1787, if asked for the meaning of a term he didn't know, and told it was being used in a law, would either ask someone he trusted who was learned in the law, or look it up in a copy of Blackstone. I find not a single instance of anyone in the era insisting on his own lay meaning over that of legally learned person. That just is not the way the people of that era thought.
The insistence on unlearned use of words in serious fields, over learned usage, is a much later development, mostly among uneducated rural Western and Southern persons in the late 19th century, and largely among recent immigrants, who felt belittled by the educated. That disdain of the uneducated by the educated and resentment by the uneducated was not a cultural divide in the 18th century. There were social distinctions, but everyone respected the educated.
Dick:There has always been tension between laity and the elites, between surrender and defiance, but the opening of the frontier of the New World transformed that tension in an important way. The bargain between laity and elites became not deference, but the lay demand that the elites persuade them by explaining what they propose and asking for their consent. They in turn agree to make the effort to understand well enough to decide wisely. That is not full expertise, but it is just enough expertise, hopefully, for a particular decision, to get through the day.
The first thing we do, let's kill all the lawyers.
Nay, that I mean to do.
Henry The Sixth, Part 2 Act 4, scene 2, 71–78
The same bargain applies to citizens, lawmakers, and law. Lay citizens don't expect to have expert knowledge of all law, just enough to make decisions in their own lives, but that includes consenting to the laws that do affect them, especially the Constitution, which affects everything and everyone.
But for making decisions in legal cases, the lay jury provides the standard. The key element, which has been largely removed from current court practice, is for all legal arguments made to the judge to also be made to the jury, not for them to decide motions of law, but to review those decisions and then either grant or withhold their consent in their verdict. It doesn't work to "protect" them from being "confused" by the legal argument. If they can be confused, then the problem doesn't lie in presentation of the legal argument, but the soundness of it. Current practice, by withholding legal argument from juries, also destroys the fundamental bargain on which constitutional legitimacy rests.
The problem, of course, is that the initial adoption of a constitution and the knowledge required to do that wisely, may not be sustained for the followthrough needed to maintain compliance indefinitely. In many ways, that requires more knowledge and talent than founding did, because there are far more competing forces to deviate from it. Our species may not be up to the challenge.