1 Introduction

Modern societies in the West are under strain. Populist politicians and parties are becoming more successful in campaigning against government policies that tended to appear self-evident in the past decades. Past policies were based on efficiency-enhancing values such as international integration and globalization, individual freedom and meritocracy (Sandel, Reference Sandel2020). Nowadays, a political divide opens up between those social groups that have internalized these values and continue supporting the respective policies and those other social groups that oppose these policies. To better understand these developments, it can be helpful to consider different facets of the social divide: differences in economic opportunities, differences in access to relevant (economic) information, as well as different levels of inclusiveness characterizing public debates. A sound analysis of how these differences interact is essential for a better understanding of some of the current tensions in modern democracies.

To this purpose, we develop an experimental model (Mäki, Reference Mäki2005) that represents in a simplified way the situation of modern societies in the West. Although we do not frame our experiment, its main application is to a situation in which societies have to choose between alternative policies, facing a potential conflict between two social groups. The state of the economy is uncertain, and while the members of one of the groups (the whites) have some information about it, the members of the other group (the blues) are uninformed.Footnote ¹ In both states of the economy the same set of policies can be implemented, which lead to different distributions of material payoffs between the groups. In one state of the world the two groups have conflicting material interests, in the other state their material interests are aligned. Hence, only the whites have some information on whether interests are conflicting. The collective choice of policy is determined through a vote in which all individuals from both groups can participate. Before the vote, the groups may communicate.

This simple setting captures modern democratic societies’ critical issue of dealing with potential economic conflicts between social groups. In most of these societies there is arguably a social class with little wealth, whose incomes are highly dependent on the thriving of the national industrial sector (the “dependent class”). In contrast, leading politicians and opinion leaders in the media, cultural and educational professions are mainly recruited from another social class that is less dependent on the national industries and more entrenched in the multi-national economic sectors (the “entrenched class”). Individuals in the entrenched class have higher education and somewhat more reliable information on economic conditions than those in the dependent class. Hence, they have an informed idea about whether their material interests align or clash with those of the dependent class, depending on the current state of the economy. By contrast, the dependent class only knows that their interests may or may not clash with the entrenched class’ interests, depending on the unknown state. How much can such a society turn their collective choice toward efficient policies? And how do truthfulness, trust, and cooperativeness between these classes develop, depending on the degree of inclusiveness that the communication channels in the society provide, e.g., the degree to which discussion panels and media are representative of both classes?

Across experimental treatments, we exogenously vary inclusiveness as follows. Pre-vote communication is determined by three distinct protocols or deliberative structures that differ in how the communication between the whites and the blues is designed. In the FullyPublic deliberative structure, we implement a stylized ideal of deliberation that is inspired by the normative deliberation literature (Dawes et al., Reference Dawes, Van de Kragt, Orbell and Mansbridge1990, Orbell et al., Reference Orbell, Van de Kragt and Robyn1988, Dryzek & List, Reference Dryzek and Christian2003): All individuals, regardless of their group affiliation, have the same possibilities of sending to and receiving messages from all other individuals. This ideal deliberative structure is the most inclusive.Footnote ² We then decrease inclusiveness stepwise: In the deliberative structure that we refer to as TopDown, only the whites have the possibility of sending messages; the blues are reduced to being receivers. However, at least in their role as receivers, whites and blues are on the same footing since each message sent is simultaneously received by all. We further reduce inclusiveness in the deliberative structure that we refer to as TopDownClosed. There, the whites first communicate among each other (“behind closed doors”) before sending messages to all.Footnote ³ For completeness, we compare these three deliberative structures to the benchmark voting game without any communication (NoChat).

Our main interest is in comparing the three implemented deliberative structures with respect to how they contribute to solving a potential economic conflict. For this to happen, in the experimental model at hand, the whites need to truthfully reveal their information to which the blues need to respond with a cooperative vote for the efficient policy, even if this is against their material interest. Building on the deliberation literature cited above, which posits that inclusiveness is essential for truthfulness and a sense of cooperation in society, we propose that different deliberative structures trigger distinct preferences in the spirit of Bowles and Polanía-Reyes (Reference Bowles and Polanía-Reyes2012). Our assumption is that a deliberative structure’s inclusiveness triggers efficiency preferences, translating into increased truthfulness and cooperativeness.Footnote ⁴ In a nutshell, we hypothesize that truthfulness and cooperativeness will be lowest in the setting without communication and increase with increasing inclusiveness of the deliberative structures.

Compared with the setting without any communication, we find that communication in all three deliberation treatments leads to more frequent choices of the efficient policies. Comparing our three deliberative structures with each other, we find that the blues are more trustful and more cooperative in FullyPublic than in TopDownClosed, which is reflected in their higher propensity to vote for the efficient policies in the former than in the latter treatment. Hence, when comparing those two extreme degrees of inclusiveness, we do find that more inclusiveness contributes to solving the economic conflict between the two groups. However, this is less clear when we compare FullyPublic and TopDown as well as TopDown and TopDownClosed. And although the whites are more truthful in TopDown than in TopDownClosed, their truthfulness does not differ significantly between FullyPublic and TopDownClosed. We then study the dynamics of the chat and voting behavior in the three deliberation treatments. We find that the dynamics of communication and behavior exhibit a general deterioration of blues’ cooperativeness and trust and whites’ truthfulness in all deliberation treatments. Moreover, in FullyPublic there is an additional factor that enforces deterioration, namely disrespectful language of the whites and uncooperative talk of the blues.

2 Related literature

Pre-vote communication has already been studied in the extensive literature on voting, recently surveyed in Palfrey (Reference Palfrey, Roth and Kagel2016). For instance, the results in Guarnaschelli et al. (Reference Guarnaschelli, McKelvey and Palfrey2000) and Goeree and Yariv (Reference Goeree and Leeat2011) document that pre-play communication in the form of either a straw-vote or unrestricted chat leads to an increase in the efficiency of the voting outcome. By contrast, Buechel and Mechtenberg (Reference Buechel and Mechtenberg2019) show that pre-vote communication in social networks that is restricted to information aggregation can lower efficiency even in a common-interest setting.

Andreoni and Rao (Reference Andreoni and Rao2011) study how pre-distribution communication affects distribution. They find that when pairs of individuals play a dictator game the distribution of the endowment varies depending on whether the allocator can send a message to the receiver or the receiver can send a message to the allocator. The receiver obtains a smaller share in the first case than in the second.

Moreover, previous experimental work has found evidence in favor of communication affecting group identity (see Akerlof & Kranton, Reference Akerlof and Kranton2000, Reference Akerlof and Kranton2010), and hence preferences. Chen and Li (Reference Chen and Sherry2009) report on an experiment in which they study the effects of induced group identity in an environment with an ingroup and an outgroup. They find that participants are more altruistic towards members of an ingroup and that chat communication within the ingroup leads to stronger ingroup favoritism. In the related experiment of Chen and Chen (Reference Chen and Chen2011) participants play a coordination game with either an ingroup or an outgroup. In one of the treatments the coordination game is preceded by a chat. They find that stronger communication—more words, more content—has a positive effect on the ingroup and a negative effect on the outgroup. Robalo et al. (Reference Robalo, Schram and Sonnemans2017) also induce ingroup bias in an experiment related to political issues without using communication. They group people according to the results of a personality questionnaire and find that political participation is higher when ingroup bias is stronger. In our case, groups are distinguished by asymmetric payoffs and access to information.

Like in our study, Palfrey and Pogorelskiy (Reference Palfrey and Pogorelskiy2017) investigate the effects of two different communication structures on voting: public communication (all voters exchange messages through a computer chat) and party communication (messages are only exchanged within each party). However, they focus on voter turnout in an experiment with costly voting. The issue of voter turnout is quite different from the research question that we address. In our environment voting is costless and, hence, is it not suited to studying turnout; indeed, we observe very little abstention in all our treatments.

Pronin and Woon (Reference Pronin and Woon2017) study how the economic benefits of deliberation can be robust to the existence of private communication between parts of the society, prior to a public discussion. In a setting in which a group of players has to allocate a fixed budget between themselves and a public good they find that allowing for private messages before the public discussion leads to the under-provision of the public good. Again, the particular issue they study is very different from ours, but the communication structure they study is related to our TopDownClosed treatment.

Although our main interest is in communication on the societal level, our analysis can also be related to the effects of institutionalized communication structures in organizational economics (Ambrus et al., Reference Ambrus, Azevedo and Kamada2013). For example, Brandts and Cooper (Reference Brandts and Cooper2007) compare the effects on coordination of various communication structures between a manager and workers.

Our novel contribution to the literature reviewed above is that we simultaneously study (1) how two groups solve a state-dependent conflict of interest, (2) how efficiently they aggregate information on that state held by one of the groups, and (3) how the conflict solution is affected by communication structures.

3 Experimental design

We consider the following voting game: Six players form a voting group, consisting of three white players and three blue players. These players vote on a policy from a set of three alternatives (A, B, and C). The implemented policy determines state-dependent payoffs that may differ by the players’ colors, see Table 1. At the beginning of the game, nature draws the state of the world, which is either X or Y with equal probability. Then, nature randomly draws an informative private signal on the state of the world for each white player. These signals are conditionally independent and true with probability $p=0.7$ . Blue players do not receive any signal.

Next, a communication stage starts. We consider three deliberative structures that vary in their inclusiveness. In particular, they gradually differ in the extent of the whites’ control over the communication process. In treatment FullyPublic, whites and blues can publicly communicate with each other. In TopDown the whites, but not the blues can send (public) messages and in TopDownClosed the whites can first communicate with each other unobserved by the blues and then send public messages that are also received by the blues. Messages are sent simultaneously, and remaining silent is possible for all senders.

Communication is implemented as computerized free-form chat.Footnote ⁵ In FullyPublic and TopDown, the chat lasted for two minutes. In TopDownClosed, both the first (private) chat among the whites and the second (public) chat lasted for one minute each.Footnote ⁶ Benchmark treatment NoChat implements our game without any communication stage. After the information stage, subjects in NoChat have the opportunity to take private notes in a computer window that looks exactly like the chat window in the other treatments. We decided to exogenously restrict the duration of the chat (note taking) stage in order to keep the total duration of the experimental sessions comparable within and across treatments. We thus tightly control the task- and time-structure of all treatments. We asked our subjects to focus their communication (in NoChat their notes) on the voting decision at hand. Apart from that, we did not impose any restrictions on their writing.Footnote ⁷

Table 1

Blue and white players’ payoffs, conditional on the state of the world and implemented policies

Policy	State X		Policy	State Y
	Whites	Blues		Whites	Blues
A	20	20	A	10	0
B	0	0	B	20	10
C	0	10	C	0	20

In the following voting stage, each individual chooses whether to vote for one of the three policies A, B, and C, or to abstain. Voting is costless. The final policy is elected according to the plurality rule (i.e., the final policy is the one that got most votes); and ties are resolved randomly, with equal probabilities.

The state of the world interacts with the implemented policy in generating final payoffs, as displayed in Table 1. In state X, whites and blues would agree on the most preferred policy: Both would like to implement policy A. This is, however, not true in state Y: While the whites would prefer B to be chosen, selfish blues would prefer C instead. Hence, the two groups have a state-dependent conflict. This conflict in state Y is particularly sharp since, for selfish whites, C is the worst of all options. The state-dependent efficient policy choice is A in state X and B in state Y. It is hence in line with the preferences of the whites.Footnote ⁸

The state-dependent conflict gives the white players an incentive to lie about the state of the world in the communication stage, if, given their signals, they expect state Y. In this case, truthfully reporting the majority signal (i.e., the signal received by the majority of whites) would lead selfish blue players to vote for C. The whites would vote for B, which ultimately generates a tie between policies B and C yielding each white player an expected payoff of $\frac{1}{2}\times 20+\frac{1}{2}\times 0=10$ if state Y prevails. If, however, the whites successfully lied about the state of the world such that the blues expected state X and hence voted for A, the whites would expect to earn $\frac{1}{2}\times 10+\frac{1}{2}\times 20=15$ if they themselves chose policy B. Obviously, and as shown in Appendix A in the Electronic Supplementary Material, successful lies cannot be part of an equilibrium here – instead, communication would become meaningless (“babbling”).

Our main underlying assumption is that deliberation works in a sense consistent with normative deliberation theory (e.g., Dawes et al., Reference Dawes, Van de Kragt, Orbell and Mansbridge1990, Orbell et al., Reference Orbell, Van de Kragt and Robyn1988, Dryzek & List, Reference Dryzek and Christian2003). Central to this theory is the idea that the more inclusive the deliberation protocol, the more inclusive become the preferences of those participating in it.Footnote ⁹ Interpreting deliberation theory, we predict that a player has selfish preferences, unless the structure of the deliberative process leads him or her to internalize the interests of others. For the blues, preferences only impact their voting. For the whites they affect both their voting and the revelation of the information they have. Based on this, we can characterize the white and blue players’ optimal behavior in our four treatments.

First, in the benchmark treatment without deliberation, NoChat, players from both groups have selfish preferences. The blues vote for C, which is the policy that benefits them most in expectation if information about the true state is absent. The whites vote for A or B.Footnote ¹⁰

Consider next the deliberation treatments, starting with the one with the lowest degree of inclusiveness, TopDownClosed, which gives the blues a passive role in the communication process and allows the whites to communicate exclusively with the other whites in the first (private) chat stage, like in the party communication treatment of Palfrey and Pogorelskiy (Reference Palfrey and Pogorelskiy2017). Supposedly, the exclusion of the blues and the in-group bias of the whites triggered by the private chat lead both groups to have selfish preferences. Then the interaction between them involves the state-dependent conflict described above, and the whites will lie to the blues if they receive majority signal Y (i.e. only babbling equilibria exist). Therefore, the blues will always vote for C, which maximizes their expected payoffs. The whites, on the other hand, will vote according to their shared information, i.e., for A in case the majority signal is X, and for B in case the majority signal is Y.Footnote ¹¹ Hence, voting behavior in TopDownClosed can be outcome-equivalent to what we predict for NoChat.

Consider next TopDown. In this treatment’s deliberation protocol, the blues have a passive role in the communication process as in TopDownClosed and, hence, only care for their own interests. However, the whites now address the society as a whole in public, without their in-group bias being triggered by the private chat as in TopDownClosed. Thus, the hypothesis based on deliberation theory is that the whites become empathetic with the blues and hence develop efficiency preferences. This makes them truthful toward both colors. As a consequence, the conflict described above is, in total, ameliorated. The whites do no longer lie to the blues about the signals they have received. Hence, in equilibrium the blues now obtain information about the true state. Following their material interests, they vote for A along with the whites when they are told that the state is X, but for C (rather than B along with the whites) when they are told that the state is Y.

Finally, consider FullyPublic. Here, both whites and blues are senders as well as receivers, as required by normative deliberation theory for an ideal deliberative structure. Our main underlying assumption implies that now both whites and blues care for both colors; i.e., they all have efficiency preferences. Therefore, the equilibrium strategies of the two colors are the following: The whites truthfully report their signals to all other players, and players vote in such a way that a plurality of votes is for A if the majority of signals indicate that the state is X and for B if the majority of signals indicate that the state is Y. Such strategy profiles implement a compromise: If state Y is more likely than X, the blues refrain from voting for their best choice C and support their second-best choice B instead, which is efficient. Given this behavior of the blues, not even selfish whites would have an incentive to lie to them about the state.

Table 2

Preferences for efficiency and their impact on information aggregation and voting decisions in equilibrium

	Whites		Blues		Efficiency preferences of		Whites’ incentive to lie	Voting given majority signal
								X		Y
	Write	Read	Write	Read	Whites	Blues		Whites	Blues	Whites	Blues
NoChat	−	−	−	−	No	No	−	A or B	C	A or B	C
FullyPublic	$✓$	$✓$	$✓$	$✓$	$✓$	$✓$	No	A	A	B	B
TopDown	$✓$	$✓$	−	$✓$	$✓$	No	No	A	A	B	C
TopDownClosed	$✓/✓$ *	$✓/✓$ *	$-/-$	$-/✓$	No	No	$✓$	A	C	B	C

*The first entry refers to the private chat among the whites, the second entry relates to the subsequent public chat. In columns $5-7$ , $✓$ indicates for each of the treatments if in equilibrium, (i) the whites and blues have efficiency preferences and (ii) if the whites have an incentive to lie to the blues

Table 2 summarizes for each of the four treatments (1) if players may read and/or write messages and (2) how the different treatments affect their efficiency preferences, (3) the incentive of the whites to lie to the blues and (4) the predicted voting decisions. In the analysis of the results we will mainly focus on the comparative statics of behavior (see Schotter, Reference Schotter, Frechette and Schotter2015), given by the last five columns of Table 2.

We conducted 20 sessions with 468 subjects from various study backgrounds at the WISO-laboratory of Hamburg University.Footnote ¹² Subjects kept their roles throughout the 20 periods of the experiment. Half of them randomly assumed the roles of white, the other half the roles of blue players. Groups were randomly re-composed and subjects’ chat IDs were randomly reassigned in the beginning of every period such that subjects were not able to track individuals throughout the different periods (stranger matching).

We used hroot (Bock et al., Reference Bock, Baetge and Nicklisch2014) to recruit subjects and coded the experiment in z-tree (Fischbacher, Reference Fischbacher2007). During the sessions payments were expressed in experimental currency units (points) which were exchanged to Euros at a rate of 1 Euro = 3 points at the end of the experiment. Average earnings for the 120 minutes sessions amounted to 23.28 Euro (s.d. 4.73), including a 10 Euro show-up fee (minimum earnings = 10 Euro, maximum earnings = 30 Euro).