I'll begin with a confession: I've only skimmed the California Supreme Court opinion upholding Proposition 8 as a permissible "amendment" that did not have to go through the more demanding process required for "revision" of the state constitution. I do not consider myself an expert in California constitutional law, in any event. Did the majority read the prior precedents too narrowly in holding that only structural changes require the revision process? Was Justice Moreno right that permitting a change that disadvantages a minority group on the basis of prejudice must itself satisfy the strict scrutiny test? That certainly would not be true at the federal level, but the federal Constitution does not distinguish between "amendments" and "revisions"---except to the extent that changes depriving any state of its equal suffrage in the Senate require a more rigorous process (obtaining that state's consent) than other changes require. I find myself having no firm opinion as to whether the case was rightly or wrongly decided based on California constitutional law.
I was struck, however, in my skimming of the majority opinion, by the following line: "In a sense, petitioners’ and the Attorney General’s complaint is that it is just too easy to amend the California Constitution through the initiative process." That may not be the entirety of the objection, but surely that does capture much of the force of the argument. One of the core purposes of constitutional democracy rather than pure majoritarianism, the objection goes, is to limit the majority's ability to oppress minoriities; permitting the majority to remove constitutional obstacles to oppressing a minority by a referendum that itself only garners a bare majority undercuts this basic constitutional function.
But if amendment by referendum is too easy, how do we know what the amendment process for any given polity should look like? Note that proponents of legal same-sex marriage (of which I count myself one) will now be thankful that they can undo Prop 8 by a simple ballot initiative. We can imagine a slightly different course of events in which Prop 8 were held invalid, but the state legislature and voters then approved an actual revision banning same-sex marriage. At that point, it might take a counter-revision to reinstate legal same-sex marriage. Whatever else we might want to say about the best amendment rules, it's hard to imagine that we could secure agreement on a rule that says "Bad changes to the constitution should be difficult to accomplish but good changes should be easy."
To the extent that I have views about how amendment/revision rules should be written, I think that one must try to take account of complex institutional interactions. A constitution that is difficult to amend (such as the U.S. Constitution) will tend to lead courts to interpret that constitution flexibly. (There is some comparative empirical evidence for this proposition that I saw presented at a conference last year but I don't have the citations handy.) Conversely, "activist" judicial interpretations, to the extent that they go well beyond popular support, will tend to lead to calls for limiting judicial power and for substantive amdendments. There are other dynamics as well. For example, Progressive-era concerns about elected officials serving the powerful led to the inclusion of the referendum as a means of amending the California Constitution.
It is thus maddeningly difficult to say anything very general about the "best" approach to constitutional change. Such matters as how judges of the high court are chosen will also play a role; even internal procedures like the filibuster rule will interact with the amendment process. In the end, I'm left with a point I sometimes tell my students (in every course I teach): Even if there is no clearly right answer, there still may be some pretty clearly wrong answers. The California system falls into the latter category.
Posted by Mike Dorf