Vik Amar has posted this draft on SSRN.  Here is the abstract:

We have now had more than a century to assess America’s initiative device, and the Progressive movement of which it was an outgrowth. Beginning with South Dakota in 1898, close to two dozen states (almost all of them west of the Mississippi) have incorporated the initiative and/or referendum into their state constitutions. Today, many states — including California, Washington, Oregon and Colorado — transact some of their most important and high-profile legislative business via direct democracy.

There is a wealth of scholarship analyzing the interface between state law direct democracy devices and the U.S. Constitution. Yet most of it has focused on a few aspects of the federal Constitution. In particular, there has been significant work done on the interplay between direct democracy and: (1) Article IV’s Republican Guarantee Clause; (2) the First Amendment’s freedoms of speech and petition; and (3) the Fourteenth Amendment’s commands of process and equal protection.

In this Essay I examine two questions of recent and looming importance concerning the way state law initiatives interact with two other important aspects of the U.S. Constitution: Article II’s delegation to state “legislatures” of the power to prescribe the method of appointing electors to the so-called electoral college, and Article III’s requirement that federal courts limit themselves to resolving only “cases” and “controversies.” In particular, I examine: (1) whether states can join the National Popular Vote Compact (NPVC) — an attempt to move the country a long way in the direction of a national popular presidential election — via initiatives rather than statutes adopted by state legislatures; and (2) whether and when official proponents (i.e., drafters and signature gatherers) of initiatives should be allowed to defend those initiatives against constitutional challenges in federal court, when the elected representatives who ordinarily defend state laws against constitutional attack – usually the Attorney General and/or Governor — decline to defend. I argue that the case against NPVC participation by initiative is relatively weak, and that states thus should be able to join the NPVC via the initiative. I also argue, using California’s Proposition 8 (a constitutional amendment banning same-sex marriage) as a case study, that although states can (and should) empower initiative proponents to defend in federal court when elected representatives decline to do so, there are important federal limits that federal courts ought to enforce regarding the circumstances under which proponents ought to be permitted federal standing to defend.