City Learning: Evidence of Policy Information Diffusion from a Survey of U.S. Mayors

• Published date: 01 March 2019
• Date: 01 March 2019
• DOI: 10.1177/1065912918785060
• Subject Matter: Articles

785060PRQXXX10.1177/1065912918785060Political Research QuarterlyEinstein et al.
research-article2018
Article
Political Research Quarterly
2019, Vol. 72(1) 243 –258
City Learning: Evidence of Policy
© 2018 University of Utah
Article reuse guidelines:
sagepub.com/journals-permissions
Information Diffusion from a
https://doi.org/10.1177/1065912918785060
DOI: 10.1177/1065912918785060
journals.sagepub.com/home/prq
Survey of U.S. Mayors
Katherine Levine Einstein1, David M. Glick1,
and Maxwell Palmer1
Abstract
Most studies of policy diffusion attempt to infer the processes through which policies spread by observing outputs
(policy adoptions). We approach these issues from the other direction by directly analyzing a key policymaking input—
information about others’ policies. Moreover, we do so by investigating policy diffusion in cities rather than states.
Using a survey of U.S. mayors, more specifically, mayors’ own lists of cities they look to for ideas, we find evidence
that distance, similarity, and capacity all influence the likelihood of a policy maker looking to a particular jurisdiction for
policy information. We also consider whether these traits are complements or substitutes and provide some evidence
for the latter. Specifically, we find that, at times, mayors eschew similarity and distance to look to highly respected
“high capacity” cities but that there is no tradeoff between distance and similarity.
Keywords
policy diffusion, local politics, urban politics, mayors
One of federalism’s virtues is the potential for lower lev-
Substantively, in light of growing partisan polarization at
els of government to act as policy laboratories for each
the federal and state levels (Abramowitz 2010; Shor and
other and for their higher-level counterparts. For this
McCarty 2011), municipalities are increasingly impor-
experimental approach to policymaking to work, state
tant venues for serious and innovative policymaking.
and local governments must learn from each other.
This is especially true for liberals and progressives,
Although a wide array of studies investigates cases of
whose recent electoral defeats at the state and federal
policies diffusing, most of this literature looks at diffu-
levels may make local government the only realistic ave-
sion by focusing on states rather than cities, focusing on
nue for the advancement of policy goals on a wide range
policy adoption rather than policy information, and inves-
of issues including minimum wage (Noguchi 2017), paid
tigating specific policy issues, usually one per study.
parental leave (Hester 2016), and environmental regula-
Previous research offers evidence that a number of mech-
tions (Biggers 2016). Given their increasing policy
anisms and/or traits such as geographic proximity (Berry
salience, it is substantively important to systematically
and Berry 1990; Mooney 2001), similarity (Butler et al.
test whether diffusion mechanisms identified at the state
2017; Grossback, Nicholson-Crotty, and Peterson 2004),
level generalize to localities. There are reasons to believe
policy success (Butler et al. 2017; Volden 2006), compe-
that they may not. Cities are constrained by economic
tition (Baybeck, Berry, and Siegel 2011), and safety in
forces and other factors (e.g., Peterson 1981), as well as
numbers (Glick 2013), along with policy attributes such
by higher levels of government, such that the policy
as salience, observability, and complexity (Boushey
areas they address, and the ways they address them, are
2010; Nicholson-Crotty 2009; Volden and Makse 2011),
significantly different from states. Moreover, while
affect policy diffusion.
recent research has highlighted partisanship in local pol-
We contribute to this literature in several ways. First,
icy (Einstein and Kogan 2016; Tausanovitch and
we explore a relatively novel locus of study: cities. While
several diffusion articles have used cities as their unit of
1Boston University, MA, USA
observation (Butler et al. 2017; Shipan and Volden
Corresponding Author:
2008), the bulk of the literature’s emphasis on states
David M. Glick, Department of Political Science, Boston University,
misses important substantive and methodological advan-
232 Bay State Road, Boston, MA 02215, USA.
tages that city-level diffusion studies can provide.
Email: dmglick@bu.edu

---

244
Political Research Quarterly 72(1)
Warshaw 2014), it has traditionally been expected to
networks might manifest as America moves into an era of
function differently in cities than in states. Finally,
progressive local government policy activism.
because cities are generally smaller and less profession-
alized than states, policy diffusion might be less system-
Theories of Policy Diffusion
atic, and the sources of policy migbt be less predictable.
Relatedly, it is also possible that the larger number of
Previous scholarship suggests a variety of mechanisms by
cities, and the diversity of city governments, induces dif-
which lower levels of government might learn from one
ferent mechanisms and correlates of diffusion.
another. Prior research contends that political actors are
Methodologically, cities offer empirical opportunities
more likely to adopt a policy already implemented by
that states and nations cannot. First, there are many more
nearby locales (Berry and Berry 1990; Mooney 2001).
of them. Indeed, medium and large U.S. cities have
This mechanism may arise because it is easier to observe
roughly six times as many potential places to learn from
what those nearby are doing, because actors compete with
than do U.S. states. This larger universe of cities confers
their neighbors for resources (Baybeck, Berry, and Siegel
value above and beyond increased sample size. It offers
2011), or because neighbors face common challenges. At
greater variation on dimensions key to testing important
times, proximity may also be an approximation of similar-
theories of diffusion. For example, states have at most a
ity (discussed subsequently). Applied to our focus on city
few neighbors, while cities will often have a multitude of
policy learning leads to the first hypothesis:
other cities nearby. Consequently, in many instances,
nearby states are fairly similar to each other, making it
Hypothesis 1 (Proximity): Policymakers are more
difficult to parse similarity mechanisms from geographic
likely to look to nearby jurisdictions.
ones. While nearby cities will often share traits, for any
given city, it is also likely that there are richer and poorer,
Proximity in the cities context may differ from its appli-
more and less diverse, and bigger and smaller cities
cation to states. On one hand, cities may have more other
nearby and far away.
cities “close by” to learn from either directly or through
Our second central contribution is that, instead of
regional networks. On the other hand, large cities rarely
studying the spread of specific policies, we look at the
have other large cities as border neighbors. Frequently,
pursuit and dissemination of policy information—a step
between two cities, one will find small cities, suburbs,
that precedes policy adoption. We ask questions about the
exurbs, and/or rural areas.
systematic (or nonsystematic) search for, and spread of,
The second main mechanism is similarity (Grossback,
policy information. Our work, thus, links to others’ stud-
Nicholson-Crotty, and Peterson 2004; Shipan and Volden
ies of information in policymaking (e.g., Mooney 1991;
2008). At the most general level, the literature suggests that
Mossberger 2000) and to the small number of other works
policymakers are more likely to enact policies after similar
that study policy diffusion through early-stage inputs
jurisdictions have done so. General agreement that similarity
rather than outputs (Butler et al. 2017; Karch 2012;
matters masks important uncertainty and disconsensus. Some
Lundin, Oberg, and Josefsson 2015).
focus primarily on political and ideological similarity (Butler
To measure cities’ sources of policy information, we
et al. 2017; Grossback, Nicholson-Crotty, and Peterson
use a novel survey of mayors, which includes respondents
2004), while others focus more on a broader but less concrete
from a wide range of cities, including many of the nation’s
notion of goal similarity (Glick and Myers 2015).
largest. Among other things, we asked mayors to list the
Moreover, disentangling similarity as a mechanism
three cities they most recently looked to for policy ideas.
from similar places independently adopting similar poli-
We also asked them why they looked to those particular
cies is challenging (Volden, Ting, and Carpenter 2008).
cities. Focusing on the universe of 288 U.S. cities with
One recent study uses a novel experiment to illustrate the
more than one hundred thousand residents, we construct a
salience of ideological similarity and policy success in
dataset with all of the actual named pairs of cities and all of
policy diffusion (Butler et al. 2017). Likewise, our focus
the unnamed, potential pairs. Populating this database with
on policy inputs helps avoid some of the challenges that
city-level geographic, demographic, and other traits, we
prior scholarship has encountered in attempting to infer
evaluate key theories in the policy diffusion literature.
similarity using observational data and policy adoption as
Specifically, we investigate whether...