Inequality and support for climate policies

The climate crisis and rising inequality are among today’s most urgent challenges. Across Europe, low- and middle-income citizens face mounting living costs, while the wealth of the ultra-rich grows. These disparities may undermine the collective action needed to tackle climate change. This study investigates how exposure to information about inequality affects support for environmental policies and willingness to act against environmental degradation, using an online experiment.

The climate crisis and growing inequalities are two of the most pressing challenges of our time. Across Europe, low and middle-income citizens are increasingly affected by the rising cost of living, while the wealth of the ultra-rich continues to grow. These disparities may undermine the collective action needed to address urgent global issues such as climate change.
The aim of this study is thus to examine how exposure to information about inequality influences support of environmental policies and willingness to act against environmental degradation. More specifically, the study seeks to establish a causal link between inequality exposure and the participants’ preferences for green policies, as well as their willingness to engage in political initiatives and give to environmental charities. We will also explore three underlying mechanisms – i.e. emotions, competitiveness/individualism and moral universalism – that might explain how inequality may influence citizens` views and attitudes towards climate policies. We will implement an online survey experiment exposing participants from different parts of Europe to information and facts about inequality with the purpose to understand how these factors influence their preferences for and decisions to supporting climate policies.

2025-06-01

2025-06-08

We will test preferences for green policies and political participation, as well as three behavioral outcomes: signing a petition, and volunteering to support environmental goals.

1. An individual's preference for green policies in society elicited through a set of non-incentivized survey questions
2. An individual's preference for political participation elicited through self-reported questions.
3. An individual's willingness to sign a petition to promote actions against climate change.
4. An individual's preference for volunteering for raising additional money to support an organization fighting climate change

We will investigate whether emotions, competitiveness/ individualism, altruism, and moral universalism act as mechanism through which exposure to inequality might influence participants readiness to support pro climate policies.

1. Emotions are elicited through the direct (self-reported) emotions questionnaire by Harmon-Jones et al. (2016)
2. Competitiveness/individualism is elicited through an effort task where participants are rewarded for correctly counting zeros in a line of numbers under time pressure. Participants can choose between a competitive and non-competitive payment scheme.
3. Moral universalism is measured through the hypothetical disinterested dictator game developed by Enke, Falk, and Becker (2020)
4. Moral universalism is additionally measured through the moral foundations questionnaire, which is based on a fixed set of self-reported questions (Graham et al. 2011); measuring moral universalism using two scientifically established instruments serves to test the validity of our findings. (subordinate study only, see experimental design)
5. We elicit altruism through a classic dictator game where participants allocate money between themselves and a random stranger (subordinate study only, see experimental design)

We conduct a main experiment as well as a subordinate experiment, where we explore one our key mechanisms in depth.

MAIN EXPERIMENT
In our main experiment, we will apply an informational treatment to investigate whether and how exposure to information about inequality may shape:
a) individual preferences for supporting climate policies;
b) individual’s willingness to take action against climate change.

Participants are randomized into two groups, one treatment group and one control group. Participants in the treatment group receive information about inequality in our society. Participants in the control group receive information about a neutral topic unrelated to inequality. In addition to testing exposure to inequality on the above listed outcomes, we test its effects on potential mechanisms including emotions, competitiveness, and moral universalism.

SUBORDINATE EXPERIMENT
In a subordinate experiment, we further explore the relationship between inequality and our candidate mechanisms to enrich our understanding of the results from the main study.

MAIN EXPERIMENT

In our main experiment, we will apply an informational treatment to investigate whether and how exposure to information about inequality may shape:
a) individual preferences for supporting climate policies;
b) individual’s willingness to take action against climate change.
We will start the experiment asking participants demographic and other social questions such as educational background and income class. After this first part of the survey, we will randomize participants into two groups, one treatment group (the information treatment) and one control group. Participants in the ‘information treatment’ group will be shown professionally produced videos about inequality. The video will describe inequality in our society by presenting facts and showcasing the different lifestyles and consumption patterns of the rich and working citizens. It will also implicitly illustrate how these two groups contribute differently to climate change (e.g., using a private jet) without explicitly mentioning climate change in the video. A subgroup will be created from the main treatment group (treatment group 2). Participants in this subgroup will watch the same video on inequality but they also will receive additional information on the unequal impact and contribution to climate change across economic group. The information used to create these videos is real, accurate, and sourced from verified sources such as Oxfam and reputable journalistic outlets. The strategy is to expose participants to the types of experiences, information, and public discussions that they and other citizens encounter in their daily lives.

After the treatment, we will first examine three potential channels through which inequality may influence the decision to take action against climate change. Then, participants will be asked questions referring to their concerns and perceptions about global challenges such as poverty, inequality, conflicts and climate change and to rank how they would prioritize these challenges to be addressed. We will also ask participants questions about their preferences concerning policies to address global challenges including climate change. Finally, participants will be asked about their willingness to engage in three specific activities: (i) signing a petition urging the government to take action against climate change, and (ii) volunteering fundraise for an organization that fights against climate change.

Our main interest is in comparing data from treatment to the comparison group. We except participants in the treatment group to be significantly more likely to adjust their policy preferences vis-a-vis the control group and reduce their willing to take any actions to address climate change. We expect that the mechanisms identified such as increasing pessimism, competition and reduction in moral universalism will help to explain the effects of inequality in the treatment group.

SUBORDINATE EXPERIMENT
We are particularly interested in moral universalism as mechanism, which describes the extent to which individuals apply equal moral consideration to others, regardless of their social proximity or group affiliation (Enke 2024). Existing literature (see Enke 2024 for a discussion) suggests that moral universalism correlates with a broad range of individual policy preferences, including support for climate policies. The main experiment does not vary the level of inequality participants are exposed to, since this is not needed to answer our main research questions. In this subordinate study, we additionally test how varying the level of inequality affects moral universalism. This allows us to investigate in-depth the interplay between inequality and moral universalism and enrich our understanding of the results from the main study.

We employ a simple between-subject design where participants are treated with differing levels of inequality by being randomized into three groups with different payment structures. Control group participants receive equal pay (show-up fee + equal bonus), participants in treatment group 1 experience a lower level of inequality (half of the participants receive a smaller bonus whereas the other half receives a larger bonus), participants in treatment group 3 experience a high level of inequality (half of the participants receive a very small bonus, the other half receives a very large bonus).

Participants are informed about their payment structure at the start of the study and then proceed (i) to play the hypothetical disinterested dictator game and (ii) to answer the moral foundations questionnaire, which are our two instruments to elicit moral universalism. We expect moral universalism to be lower in treatment group 1 and 2 than in the control group. Next, we elicit people's altruism through a classic dictator game, where they allocate money between themselves and a random stranger from our participant pool. In a last step, we elicit people's preferences for green policies, political participation, and signing a petition to fight climate change.

Randomization method: We use the built-in randomizer in Qualtrics, the survey software we are using to implement the experiment online.

Observation unit, i.e. our unit of analysis: individual survey participants

No

The design is not clustered, it is implemented at the individual-level.

Based on our power calculation, our sample will include 5900 individuals living in 5 European countries i.e. France, Germany, Italy, Spain and UK

Main Experiment: 2000 individuals in the control group, 2000 individuals in the treatment group 1 and 1000 individuals in the treatment group 2

Subordinate Experiment: 300 individuals in the control group, 300 individuals in treatment group 1, and 300 individuals in treatment group 2