Legislative Constraints on Executive Unilateralism in Separation of Powers Systems

• Author: Alexander Bolton,Michael Barber,Sharece Thrower
• DOI: http://doi.org/10.1111/lsq.12232
• Published date: 01 August 2019
• Date: 01 August 2019

515

LEGISLATIVE STUDIES QUARTERLY, 44, 3, August 2019

DOI: 10.1111/lsq.12232

MICHAEL BARBER

Brigham Young University

ALEXANDER BOLTON

Emory University

SHARECE THROWER

Vanderbilt University

Legislative Constraints on Executive

Unilateralism in Separation of

Powers Systems

Can legislatures effectively check unilateral executive power? One promi-

nent and counterintuitive finding in previous work is that executives pursue

unilateralism less often under divided government. While executives see greater

potential policy gains through unilateral action during divided government, we

argue that their likelihood of acting unilaterally depends on an opposed legisla-

ture’s ability to retaliate. When polarization is high and majorities are marginal,

executives are freer to act unilaterally given the difficulties legislatures have in

statutorily responding. Unilateralism is also more likely when facing opposition

if legislatures lack nonstatutory means of punishment, such as regulatory review.

In the largest analysis of gubernatorial executive unilateralism to date, we use a

new data set of 24,232 executive orders in the 50 American states between 1993

and 2013 to evaluate this argument and find strong support for its predictions.

These results provide insights into how legislative policymaking capacity can in-

fluence the functioning of separation of powers systems.

Introduction

For centuries, institutional designers have debated the

merits of distributing power between a legislative and executive

arm of government (Hamilton, Madison and Jay 2009; Lijphart

2012; Montesquieu 1949; Tsebelis 1995). A primary argument

for these arrangements lies in the ability of each governmental

branch “to be the means of keeping each other in their proper

places” (Hamilton, Madison, and Jay 2009, 263). The degree to

which legislatures shape the exercise of executive power and the

© 2019 Washington University in St. L ouis

516 Michael Barber, Alexander Bolton, and Sharece Thrower

mechanisms that underlie legislative influence on executives are

questions of paramount importance in separation of powers sys-

tems. In few other realms is this concern so central as i n the exer-

cise of unilateral power, where executives may have a seemingly

unfettered ability to bypass the legislative process in pursuit of

their own preferred policies. The degree to which they limit their

unilateral behavior in response to legislatures is potentially vari-

able and relevant in a diversity of contexts , from the use of dec ree

powers by Latin American presidents (e.g., Shair-Rosenfield and

Stoyan 2017) to the issuance of presidential and gubernatorial

executive orders in the United States (e.g., Mayer 2002; Sellers

forthcoming).

There are frequently conflicting views on this issue. Public

perception and media commentary in the United States, for in-

stance, often suggest that executives are able to freely use unilat-

eral actions as a way to sidestep and evade ideologically hostile

legislatures.Yet studies of unilateral polic ymaking most often f ind

evidence to the contrary: Presidents issue fewer executive orders

under divided govern ment (e.g., Chiou and Rothenberg 2017; Fine

and Warber 2012; Young 2013), suggesting they curb their unilat-

eral activity when their preferences are the most divergent from

Congress. In th is article, we seek to better unde rstand the mecha-

nisms that underlie these seemingly counterintuitive results and

examine circumstances in which they do and do not hold.

We build upon previous theories of unilateralism and argue

that legislature s possess, under p articular c ircumstanc es, the insti-

tutional mechan isms and powers (which we refer to as policymak-

ing capacity) necessary to induce executive restraint. Legislative

majorities high in policymaking capacity can retaliate against

executives who pursue unilateral policies that make them worse

off relative to the status quo. This has important inc entive effects

for executives. Previous work has highlighted periods of divided

government as times when executive incentives for unilateralism

may be tempered by legislatures. We argue that this relationship

is contingent on the legislature’s ability to effectively respond to

unfavorable policy changes and identi fy specific me chanisms that

can produce patterns of constraint (and evasion). In this way, the

divided government findings are not universal; rather, they de-

pend on important factors in the political environment.

In brief, we argue that legislatures are inhibited from act-

ing statutorily to counter the executive when ideological polari-

zation is high or supermajoritarian veto-override thresholds are

517Legislative Constraints on Executive Unilateralism

insurmountable. Furthermore, when nonstatutory sanctions on

the executive are unavailable to legislatures, their relative power

is also diminished. In these cases, we argue that executives face

few credible constraints from legislatures controlled by the op-

posing party a nd can thus more freely act unilater ally, in line with

the “evasion” view of unilateralism. However, in the presence of

large, unif ied majorities or signif icant extrastatutory tools, execu-

tives are hemme d in by legislatures, and less un ilateralism should

occur during divided government relative to unified. In other

words, executive reactions to partisan division are conditional

on the policymaking capacity of legislatures. Although previ-

ous studies have identified the importance of internal legislative

fragmentation (e.g., Howell 2003) and extrastatutory mechanism s

of constraint (Chiou and Rothenberg 2017) in shaping executive

unilateralism, they largely do not examine how these factors can

moderate the effect s of divided government. Thus, our study con-

tributes to this literature by delineating the conditional effects of

these factors to identi fy important mechanism s for why and when

executives adjust their un ilateral strategies in the face of partisan

opposition.

We evaluate this theory with an original data set of nearly

25,000 gubernatoria l executive orders from all 50 states issued b e-

tween 1993 and 2013. Focusing on the United State s has a number

of advantages over prior empirical investigations of unilateral-

ism. Most previous work has examined a single time series at the

federal level in the United States, leading to concerns about gen-

eralizabi lity and lack of variation in key theoretica l variables. For

instance, nonstatutory powers are mostly constant at the federal

level, offering little empirical leverage on their effects. Other key

variables, such as polarization, evince far more variation in both

magnitude and trends in the states. Fur thermore, veto-proof ma-

jorities are incredibly rare in Congress, making it difficult to di-

rectly study veto power. We leverage this variation in the states

to better identify the effects of interbranch partisan divergence

on unilateralism and the mechanisms underlying it. As such, we

offer the most extensive comparative study of executive order

use to date, demonstrating the utility and generalizability of our

theory. Our empirical results offer confirmation of our argu-

ment, suggesting that executives reduce unilateralism when fac-

ing divided government—but not always. Instead, we show that

the relationship between interbranch conflict and unilateralism

is contingent on a number of institutional factors. In doing so,