During the third week of April 2013, terrorists detonated bombs at the finish line of the Boston Marathon and a watered-down gun control bill failed to pass the Senate. President Obama, who favored much stronger restrictions on weapons than those proposed by the Senate bill, did not respond to his political defeat by declaring the sort of an emergency that might warrant an executive decision to implement his preferred gun control policy. The president did not order the Justice Department to interpret existing restrictions on various weapons as, in fact, incorporating the proposals his administration made to Congress in previous weeks. President Obama did little more than complain about Congress to the press and American people, in the hopes of inspiring more favorable legislation in the future.

Obama's timid behavior might surprise readers of Eric Posner and Adrian Vermeule's The Executive Unbound: After the Madisonian Republic. This book claims that in the contemporary administrative state, Congress and the federal judiciary no longer have meaningful power to check the executive. The authors declare, “we live in a regime of executive-centered government” in which “the legally constrained executive is now a historical curiosity” (4). Posner and Vermeule do maintain that informal political checks are substitutes for formal legal checks. The Executive Unbound asserts, “even an imperial president is constrained by politics and public opinion” (12) and that while these political checks function differently than legal checks, they are at least as effective as means of preventing presidential tyranny. These political checks prevent presidents from implementing unpopular policies. The question readers of The Executive Unbound are likely to ask is why presidents often do not unilaterally implement fairly popular policies that are blocked in Congress. Certainly public opinion in the wake of the Boston Marathon and Newtown does not explain why Obama refrained from ignoring legal constraints on his capacity to unilaterally mandate tighter gun control regulation.

Posner and Vermeule do not furnish a compelling answer to this question. They stand charged with stating their thesis more boldly than their evidence actually warrants—a crime committed by at least half the authors of major university press books in the United States. The Executive Unbound is an important contribution to constitutional thinking about the changing nature of executive power in the contemporary world. Congress and courts matter far more than some passages in the text suggest, but Posner and Vermeule correctly point out and explain why traditional legal restrictions matter far less than many contemporary lawyers would like and why prominent proposals for creating more legal restrictions on presidential power are unlikely to be successful.

Posner and Vermeule champion the Carl Schmitt revival in contemporary constitutional thinking. One central tenet of Schmittian constitutionalism is a belief that the modern administrative state renders the traditional separation of powers and rule of law obsolete. Governments must constantly manage and respond to frequent emergencies, tasks that cannot be achieved within rule of law principles that emphasize adherence to obsolete statutes passed in response to past conditions. The Executive Unbound, while firmly disavowing the ugly features of Schmitt's work (Schmitt believed that politics was an unremitting struggle between enemies, disparaged liberalism, and supported Hitler's rise to power), points to numerous features of American politics that support Schmitt's constitutional vision. Posner and Vermeule correctly highlight how much administrative law violates traditional rule of law standards. Congress delegates huge swaths of policy-making either to the executive or to independent administrative agencies without clear guidance. Standard forms of legislative oversight do not work; many elected officials do not have the incentives to make oversight work. Motivated representatives lack the information and other resources necessary for overseeing intelligently executive and administrative officials. The judiciary is a poor substitute for Congress. On some matters, courts have adopted rules that certain administrative decisions are unreviewable. On most other matters, judges adopt such deferential legal standards that for all practical purposes administrative decisions are unreviewable.

Matters are even worse from a traditional rule by law perspective when foreign policy and financial crises occur. On such issues, Schmitt, Posner, and Vermeule observe that legislatures “come too late” (19). Typically, the emergency requires the executive to take actions that are, at best, borderline legal, largely because the particular emergency was not foreseen by previous legislators and legislation. By the time the legislature participates, commitments have already been made. Little deliberation then takes place, given the need for speed. Instead, Congress almost always retroactively approves what the president is doing, gives the president power to do more, and at most tinkers at the margin with presidential decisions. Congress has neither the capacity nor motivation to do better. The nature of emergencies, not the peculiar failures of particular legislators and legislatures, are responsible for the new administrative state and the destruction of separation of powers logic.

Fortunately, Posner and Vermeule maintain that contemporary presidents who experience few legal constraints still confront substantial political barriers to unilateral action. Presidents need popularity both to accomplish their goals, whatever they may be, and to gain reelection. This need for popularity inhibits presidential action outside the pale of public opinion. Posner and Vermeule debunk claims that the lack of legal constraint threatens Americans with a fascist form of presidential dictatorship. “Tyrannophobia” (176), they state, is a distinct American paranoid fantasy that fails to recognize the reality that the very forces that subvert the rule of law in an administrative state also foster the affluent society necessary to maintain a democratic order. The “Demographic and economic conditions” that “produce … the administrative state,” The Executive Unbound contends, “also help to produce a wealthy and highly educated population, whose elites continually scrutinize executive action and tighten the constraints of popularity and credibility” (14).

Law matters more in Vermeule's The Systems of the Constitution. The Executive Unbound details how law rarely constrains presidents when conflicts arise between the executive and other branches of the national government. The Systems of the Constitution details how constitutional text helps determine who engages in constitutional conflicts, the incentives that structure their conduct, and what policies governing-officials dispute. Vermeule stresses that constitutional orders are best understood as a series of systems embedded in a broader system. Just as a particular system may have different properties than any individual member of the system, so the constitutional system as a whole may have different properties than any particular constitutional institution. The Condorcet jury theorem explains why large groups have capacities to make accurate decisions that individual members lack. The Constitution as a whole, Vermeule similarly argues, may be more democratic than any particular constitutional institution. The democratic defects of one institution may compensate for different democratic defects in another institution.

Both The Executive Unbound and The Systems of the Constitution eschew claims that constitutions function primarily by providing legal constraints on political actors. Vermeule details how constitutions function by constructing politics. Constitutions create incentives for some kinds of behavior and disincentives for others. The ways in which constitutional systems and the Constitution of the United States aggregate individual decisions and various institutional outputs make some outcomes far more likely than others. Constitutions matter, but the provisions that matter are the structural clauses that facilitate certain behaviors rather than such provisions as civil liberties guarantees, which can be interpreted in various ways.

Numerous insights in The Systems of the Constitution are particularly fascinating. Vermeule does a wonderful analysis of invisible hand claims, the claim that a particular system will generate a good (or any particular) result, even though no member of that system acts for the purpose of obtaining that result. Another section details the influence of such rarely analyzed clauses as the Compensation Clause on constitutional practices. Some methods for paying officials encourage candidates temperamentally suited to sustain the constitutional order, while other payments systems provide officeholders with incentives to undermine the constitutional order. The last substantive chapter explains why a judge committed to some methods of constitutional exegesis might nevertheless adopt another in order to achieve best results. Vermeule states, “texualism justified on democracy-forcing grounds will be pointless, or even perversely harmful, unless and until some critical mass of other judges goes along” (141).

The Systems of the Constitution suggests how The Executive Unbound may not fully appreciate how the Constitution constrains different presidencies. Vermeule elegantly demonstrates that constitutional systems are not neutral. Posner and Vermeule in The Executive Unbound write that a Congress limited to “modifying and occasionally blocking executive initiatives … play[s] an essentially reactive and marginal role.” In fact, if one emphasizes, as Vermeule does in The Systems of the Constitution, how the Constitution constructs politics, the impact of checks and balances varies depending on the executive initiative in question. An executive bent on an aggressive foreign policy often needs only passive legislative acquiescence. President Barack Obama, by comparison, requires active legislative support to achieve his progressive domestic agenda. Hence, he faces far more separation of power constraints when seeking gun control reform and health care legislation than former President Bush did during the Iraqi invasion. In short, even if congressional power to check the president has waned, the Constitution constructs politics in ways that enable Congress to check some presidents and presidential initiatives more effectively than others.

The Executive Unbound and The Systems of the Constitution demonstrate the strengths and weaknesses of rational choice and economic analyses of the law as practiced in the legal professoriate. Both works are extremely well written—unlike many social scientists, who obscure important findings by overuse of over-technical language, Posner and Vermeule write in an engaging, accessible fashion. Their arguments are lucid and easy to follow, even for a novice, with each book providing important insights on separation of powers and constitutionalism. The main weakness of each volume is the tendency, common to practitioners of economic analysis across disciplines, to substitute rational speculation for closer examination into historical sources. The clearest example of this occurs in The Executive Unbound when Posner and Vermeule explore why the Declaration of Independence is directed against the King of England, rather than Parliament. Without citing a primary or secondary source, they claim that Jefferson refrained from criticizing Parliament because the colonists wished to retain strong ties to England after the revolution. Historians, after examining primary sources, maintain that the colonists by 1776 concluded that Parliament had no right to rule over the colonies; the King was the only British entity authorized to make policy. Hence, while colonial documents published in the 1760s complain about Parliamentary rule, both the Declaration of Independence and Tom Paine's Common Sense focus their antipathy on the King.

Flaws common to the genre aside, these works serve as an important reminder that parchment barriers in 2013 function no better than Madison expected parchment barriers to function in 1787. Persons who read only the constitutional and statutory text cannot understand how the modern presidency and administrate state function. Posner and Vermeule catalogue how legal barriers against presidential action are simultaneously weakening and diminishing. Vermeule astutely points out that constitutional provisions often function by constructing politics than by compelling presidents to refrain from taking desired actions. Both books might have noted how constitutions, in addition to constraining and constructing politics, also constitute politics by helping to create interests and establish background norms that all parties take for granted. Even in the administrative state, the president stands for reelection every four years, exactly as the Constitution prescribes. President Obama's commitment to the broadly accepted rules of the game probably best explains why he does not even seriously contemplate unilaterally enacting gun control reforms after Congress rejects his proposals. Some actions in a well-constructed constitutional regime are simply not done, even if an outside economist might suggest that a rational person might act otherwise.