# Green Astroturfing Unpacked: The Moral Judgment of Direct and Indirect Tactics

Safaa Adil, Gilles Grolleau, Naoufel Mzoughi

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Safaa Adil, Gilles Grolleau, Naoufel Mzoughi. Green Astroturfing Unpacked: The Moral Judgment of Direct and Indirect Tactics. International Journal of Business Governance and Ethics, In press. *hal-05298833*

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Green Astroturfing Unpacked: The Moral Judgment of Direct and Indirect Tactics

Safaa Adil

ESSCA School of Management, Angers, France

[safaa.adil@essca.fr](mailto:safaa.adil@essca.fr)

Gilles Grolleau

ESSCA School of Management, Lyon, France

[grolda@gmail.com](mailto:grolda@gmail.com)

Naoufel Mzoughi (Corresponding author)

INRAE, ECODEVELOPPEMENT, Avignon, France

[naoufel.mzoughi@inrae.fr](mailto:naoufel.mzoughi@inrae.fr)

Acknowledgment: The authors are grateful to Leonith Hinojosa, Lisette Ibanez, and Emeline Martin for their useful comments and suggestions.

Conflict of interest: none.

No funding.
# Green Astroturfing Unpacked: The Moral Judgment of Direct and Indirect Tactics

**Abstract:** Some companies use deceptive tactics to persuade people that a particular position or recommendation has widespread support and originates from grassroots movements—a phenomenon referred to as astroturfing. We demonstrate that astroturfing exploits basic human heuristics to advance the sponsor's interests, often undermining genuine efforts to address environmental challenges. Moreover, we examine the moral seriousness of green astroturfing in a business-related context and test experimentally whether individuals perceive it differently when it originates directly from the company vs. through an intermediary. We find that moral judgment and recommended punishment for green astroturfing are significantly higher when the company outsources it.

**Keywords:** green astroturfing; moral judgment; public opinion; punishment.

## 1. Introduction

Astroturfing is a deceptive strategy used by some interest groups (e.g., corporations, political parties) to persuade specific third parties (e.g., politicians, consumers, constituents) or the public that some positions or arguments come from grassroots movements. Astroturfing involves orchestrating seemingly grassroots campaigns that conceal the true sponsors of a message (Skiba et al., 2019; Lits, 2021; Kinder, 2024) and can operate on various scales, from local to global. For instance, Monsanto, a US agrochemical company, funded fake farmers' groups in various countries (e.g., *Free to Farm* in the United Kingdom, *Agriculteurs et Liberté* in France, *Libertad para Cultivar* in Spain) to promote and defend its herbicide Roundup (Glyphosate). These counterfeited grassroots-led campaigns were particularly active when the European Union was considering the authorization renewal of the controversial herbicide. Once the role of Public Relations (PR) firms working for Monsanto was publicly
disclosed, the online presence (e.g., websites, social media accounts) and offline support of
these fake groups quickly disappeared.

In practice, astroturfers are often very creative and use a variety of tricks, such as fake
reviews and testimonials (companies may create fictitious accounts to post positive reviews
about products or services, thereby creating an illusion of consumer satisfaction),<fnref n="1" /> coordinated
social media campaigns (utilizing bots or paid individuals to amplify specific messages,
which can create a false sense of grassroots momentum), and influencer partnerships
(collaborating with influencers who may not disclose their financial ties, thereby misleading
audiences into believing that endorsements are genuine personal opinions rather than paid
promotions) (see, e.g., Schneider, 2015; Kinder, 2024; Yin et al., 2025). In the same vein and
contrary to what their (euphemistic) denominations might indicate, the *National Wetlands
Coalition, Global Climate Coalition, Greening Earth Society, and Responsible Energy
Citizens Coalition* are not real environmental or citizen NGOs, but astroturf groups,
concealing corporate interests to campaign against regulating various environmental issues
(Grolleau et al., 2022). This multibillion-dollar business undermines initiatives to address
environmental challenges at various levels and generates a distrusting society, where even
legitimate voices become suspect (Beder, 1998; McNutt and Boland, 2007; Lits, 2021;
Kinder, 2024; Hartley, 2025).

This tactic has gained importance, especially in online environments, where using
euphemistic framing is pervasive, and detecting the real origin of messages can be very
difficult (Kovic et al., 2018). Indeed, the internet offers astroturfers an ideal environment
where they can work on a large scale under a cloak of anonymity. New technologies such as
social bots allow to imitate grassroots movements on an impressive scale and shape public

<footnote n="1">¹ In a survey of 1,672 business owners, 18.3% reported they would consider undermining a competitor's online presence—such as by posting fake negative reviews—if they could do so without consequences (Wooten, 2020).</footnote>
opinion (Weiss, 2019). For instance, some telecommunications enterprises paid astroturf companies (e.g., Fluent, Opt-Intelligence, and React2Media) to generate millions of fake public comments in favour of ‘net neutrality’ and discredit genuine voices of dissent. These astroturfers “stole people’s names and email addresses from old files and hacked data dumps and attached them to 8.5 million public comments and half a million letters to members of Congress” (Farrell and Schneier, 2021). Other illustrative examples related to environmental and non-environmental domains are reported in Box 1 (see also Beder, 1998; Schneider, 2015; Kinder, 2024).

[Insert Box 1 around here]

Interestingly, although there is some overlap between “fake news” and astroturfing, they represent different phenomena in the realm of information dissemination (Chan, 2024). While fake news corresponds to false statements, in the case of astroturfing, the root of the deception relates to the source, underlying support, and validation of what is communicated (Chan, 2024). Astroturfing refers to orchestrated efforts that create a false impression of grassroots support for a particular agenda or product. This distinction does not mean that the content of astroturfing statements or actions is true. Frequently, it is false, and sometimes it cannot be classified as either true or false. For example, a corporation might sponsor social media campaigns that appear to be grassroots movements advocating for a specific policy that benefits them, thereby obscuring their true interests (Schneider, 2015; Kinder, 2024). Some astroturfing tactics may simply imply ‘following’ an X account, ‘liking’ some tweets posted by a personality, or ‘booing’ some competitors, without communicating substantive elements. Indeed, the power of astroturfing lies in the ability to generate ‘coordinated inauthentic behaviour’ (e.g., a high number of seemingly genuine followers or authentic likes) to persuade their targets (Chan, 2024). This deceptive appearance of grassroots support for a particular cause or specific agenda seeks to subtly manipulate public perceptions about the authenticity and source of the message by suggesting widespread authentic support when, in
fact, it is artificially manufactured (Schneider, 2015; Zerback and Töpfl, 2022; Chan, 2024).

Fake news, on the other hand, typically involves the deliberate spread of misinformation or disinformation—content that is factually incorrect or misleading. While both practices seek to influence public opinion, astroturfing does so through a façade of legitimacy rather than outright falsehoods. Interestingly, while fact-checking is often positioned against fake news, the need for transparency regarding both genuine and manufactured support, sponsorships, paid promotions, and similar practices is frequently emphasized to protect consumers from astroturfing attempts.

Given the importance of astroturfing combined with a relative lack of economic studies on this phenomenon, the objectives of this article are twofold. First, using behavioural lenses, we conceptualize astroturfing as a strategy to exploit some heuristics (notably in-group, multiple source, and illusory truth biases) to cover the tracks and serve the vested interests of astroturfers (Zhang et al., 2013). Indeed, astroturfing frequently relies on a double deception: (i) the astroturfers mask their identities, sponsors, and goals and make their audience believe they emanate from grassroots movements, and (ii) the arguments do not correspond to what the legitimate grassroots movements endorse and break the image of a united front (see, e.g., Lyon and Maxwell, 2004). Given the hidden nature of astroturfing operations, the disclosure of arrangements is very unlikely. At the same time, the stakes are very high because this unchecked and illegitimate influence can obstruct and neutralize regulations aimed at solving critical global problems (Durkee, 2017).

Second, businesses use various strategies to distance themselves from astroturfing and mislead their audience. One such strategy is to outsource astroturfing operations to an intermediary, such as a public relations company (Schneider, 2015). Hence, we explore empirically the moral judgment of direct versus indirect astroturfing by examining how lay observers judge the morality of an identical astroturfing operation that differs only by whether the company performs it or outsources it to an intermediary. Understanding the moral
judgment of direct versus indirect astroturfing is essential to determine whether individuals
are more lenient toward certain forms of astroturfing. Such leniency could inadvertently
provide astroturfers with a moral pass, enabling them to persist in unethical practices and even
expand their activities—particularly in a post-truth world (Effron and Helgason, 2022).
Furthermore, this insight sheds light on the moral risks that can jeopardize a company’s
‘social license to operate’ (Gehman et al., 2017), especially from a long-term perspective.

Several papers have used survey experiments to explore research questions related to astroturfing—particularly how laypeople or specific groups perceive, respond to, or are influenced by it—as well as to test approaches for countering astroturfing attempts (e.g., Cluverius, 2017; Zerback et al., 2021; Wagnsson et al., 2025). For instance, Cluverius (2017) conducted a survey experiment that challenges the notion that legislators count email responses as a latent measure of issue salience. The study found that the volume of lobbying messages has no effect on legislators’ responses to high-salience issues and even has a negative effect on responses to low-salience issues. Zerback et al. (2021) examined the psychological effects of online astroturfing in the context of Russia’s digitally enabled foreign propaganda. They found that astroturfing comments can influence recipients’ opinions and increase uncertainty—even when participants were inoculated prior to exposure. Similarly, Wagnsson et al. (2025) used a survey experiment to investigate whether framing unreliable information as a foreign threat can improve the effectiveness of media literacy training while minimizing excessive scepticism toward trustworthy sources (see also Boman and Schneider, 2021).

Using a similar empirical approach, our paper explores a related yet distinct direction
by examining the comparative severity of moral judgment and perceived deservingness of
punishment when observers are informed about direct versus indirect green astroturfing—an
underexplored area in both business ethics and the psychology of deception. While previous
research has examined deceptive practices in political and corporate contexts, our study
uniquely highlights how the use of an intermediary to carry out the deception influences
moral evaluations and recommended punishment.

The remainder of this article is as follows. In Section 2, using a behavioural lens, we analyse astroturfers as exploiters of human mental shortcuts. Section 3 is devoted to the moral judgment of direct versus indirect astroturfing. In Section 4, we present the experimental survey designed to explore the latter issue and discuss the main findings. Section 5 draws some implications and concludes.

## 2. Astroturfing as an exploitation of heuristic shortcuts

A behavioural lens, centred on biases and heuristics, is particularly well-suited to analysing astroturfing, given the reliance of human decision-making on cognitive shortcuts and social pressures. For example, when individuals observe widespread support for a cause, they may feel compelled to conform (Cialdini, 2007; Farrow et al., 2017; Chan, 2024; Fagan, 2024), interpreting popularity as an indicator of validity. Understanding these biases allows for a deeper moral analysis of how targeted individuals perceive and respond to astroturfing efforts. This framework not only clarifies the mechanisms underlying astroturfing but also illuminates the moral judgments associated with such manipulative tactics. Recognizing these biases is also critical to developing effective counter-strategies and fostering media literacy.

In what follows, we discuss some of the heuristics commonly exploited by astroturfers to advance their vested interests at the expense of their targets, namely the in-group persuasion effect, the multiple source effect, and the illusory truth effect.<fnref n="2" /> Rather than

<footnote n="2">² These shortcuts are not intended to be exclusive neither exhaustive. They were selected because we contend they are the most relevant in this context. However, other heuristics maybe at stake to influence public opinion. For instance, the authority bias refers to the tendency of individuals to trust and follow opinions or claims made by figures perceived as authoritative or credible (Milgram, 1963). Endorsements from fake experts, organizations, or influential personalities can lend undue credibility to deceptive campaigns.</footnote>
encouraging slow, deliberative, and effortful information processing, such as cost-benefit analysis (System 2 thinking), astroturfing relies on rapid, intuitive, and effortless heuristics (System 1 thinking) (Kahneman, 2011). This strategy leads targets to draw conclusions about the validity of a position without critically evaluating its merits.

First, astroturfers harness the *in-group persuasion effect* by presenting themselves as belonging to the same group as the targeted audience (e.g., citizens from the same location, same political orientation, or with a shared identity) or as members of a trustworthy group (e.g., scientists, environmental activists) (Mackie et al., 1992). Moreover, people frequently use the source credibility cue and deduce the credibility of provided information from the believability of its source (e.g., Go et al., 2014). It is also well-known that people easily agree to arguments that support their prior opinion, but vehemently obstruct opinion-incongruent arguments (Kunda, 1990). For instance, some pro-fracking astroturf movements mobilized the sense of place to advance their agenda (Lloveras et al., 2021). Denominations such as “*Americans for Balanced Energy Choices*” or “*Energy Citizens*” convey the first impression that they are just disinterested groups of citizens willing to speak frankly about crucial public issues, while they are not. Accordingly, people are less likely to engage in critical scrutiny of messages when these messages are perceived as originating from credible front groups that have widespread support. The shared social identity and perceived authenticity and credibility of the source constitute a “heuristic cue” that allows one to assess the soundness of a persuasive message (Ziegler et al., 2004; Grolleau et al., 2022; Chan, 2024). For instance, individuals tend to be particularly receptive to word-of-mouth communications due to their perceived authenticity and relatable nature, especially since these messages originate from peers (Bickart and Schindler, 2001; see also Schneider, 2015). This trust stems from the assumption that fellow consumers or citizens, unlike companies that stand to benefit from having a prospect believe something positive about themselves or their product, have no
vested interest in providing misleading information and are motivated solely by a desire to
share their genuine experiences (Fong and Burton, 2006).

Second, astroturfers also mobilize the bandwagon or *multiple source effect* to increase their persuasion power compared to a single source (Harkins and Petty, 1987; Zhang et al., 2013; Leiser, 2016). Indeed, people frequently follow the crowd and use the apparent approval by others or the popularity of something as a shortcut to evaluate its significance and quality (Cialdini, 2007). In the same way, astroturf organizations frequently organize events (e.g., rallies, protests) with several hundred fake disinterested citizens, scientists, and coalitions of front groups (Beder, 1998; see Schneider, 2015 and the company website https://crowdsondemand.com/). To give flesh to their claims, these operations mobilize corporate employees or paid individuals to play the game. These influential events are frequently amplified by well-organized media coverage. These approaches also use more and more artificial intelligence, which facilitates the creation of fake identities and the generation of huge numbers of personalized messages (Farrell and Schneier, 2021). By presenting themselves as genuine grassroots voices that want to be part of the solution by advocating alternative propositions (e.g., “clean coal”), they purposefully persuade the public or more specifically targeted audiences (Kinder, 2024).

Third, the *illusory truth effect* involves repeated exposure to a statement, which increases its perceived truthfulness, regardless of its accuracy (Hasher et al., 1977; Udry and Barber, 2024; see also Stump et al., 2025). By frequently repeating false or contestable claims across various channels, astroturfers make their narratives appear more credible over time. Interestingly, the recent contribution by Udry and Barber (2024) posits that repetition has broader impacts beyond belief, such as increasing sharing intentions and decreasing the perceived unethicality of an act. Ironically, astroturfers may benefit from these sharing tendencies, increasing the perceived grassroots support (crowd sentiments are self-reinforcing; Chan, 2024) and reducing the perceived unethicality of the advanced position. In
short, given that astroturfers often have the resources to provoke repeated exposure to a given statement, they can harness the illusory truth effect to surreptitiously advance their vested interests.

**3. The moral judgment of (direct versus indirect) astroturfing**

Given that mental shortcuts are often exploited to subtly manipulate individuals, it is crucial to understand how people, as potential victims of astroturfing, form moral judgments about such manipulative acts once they are revealed. When people become aware of heuristic-based attempts to manipulate them, they are likely, at least in a first approach, to rely on System 1 thinking to form intuitive moral judgments (Haidt, 2001). Rationalist models of moral judgment posit that ethical decisions arise from deliberate and conscious moral reasoning (Kohlberg and Hersh, 1977; Rest, 1986). From this perspective, individuals engage in System 2 processing—characterized as slow, controlled, effortful, rational, and rule-governed—to arrive at moral judgments. They deliberate consciously, applying consistent principles, and weigh various ethical considerations and potential consequences. Scholars, such as Kohlberg and Hersh (1977) and Rest (1986), argue that moral development progresses through distinct stages as individuals develop greater capacity for complex moral reasoning.

In contrast, social intuitionist models suggest that moral reasoning does not drive moral judgment but rather follows it. According to these models, moral judgments stem from System 1 processing, which is fast, automatic, effortless, and associative (Haidt, 2001). These judgments are shaped by intuitive, rapid responses influenced by seemingly irrelevant factors, such as the use of euphemisms (Farrow et al., 2021) or the physical and psychological distance at which a decision is made (Grolleau et al., 2023). From this perspective, moral deliberation often serves as a post hoc justification for the intuitive judgment.

Interestingly, Haidt's social intuitionist model shares notable parallels with the biases and heuristics framework. Both emphasize automatic and rapid processing, the limited role of
conscious reasoning, the influence of emotions, biased reasoning, and the impact of social and cultural factors. These similarities highlight a shared understanding of human cognition as predominantly driven by intuitive, automatic processes susceptible to biases and social influences.

When people discover attempts to manipulate and deceive them to serve vested interests, their reactions are likely to be very negative and may involve several psychological and behavioural responses (see Cho et al., 2011 for a more nuanced perspective), such as opposition or counteraction—public outcry, boycotts, or negative word-of-mouth (Lyon and Maxwell, 2004; Kang et al., 2016; Skiba et al., 2019)—exhibiting reactance and a desire for retribution by punishing the perpetrators or actively working to undermine the manipulator's goals (Kang et al., 2016; Skiba et al., 2019; Balbuzanov, 2019; Roozbahani et al., 2022). These responses are not mutually exclusive and often occur in combination, creating a multifaceted negative reaction.

Interestingly, social intuitionism suggests that seemingly irrelevant details can affect moral judgment, such as whether the judgment of a similar unethical act by observers is perceived and judged differently when it is carried out directly by a specific agent versus indirectly through an intermediary. The use of an intermediary can be perceived as an additional attempt to deceive by distancing the initiator from the unethical act. This heightened perception of manipulative intent may provoke emotionally charged reactions. Moreover, greater psychological distance is thought to promote a more abstract construal of the situation, which can also lead to harsher moral judgments (Eyal et al., 2008; Trope and Liberman, 2010; see also Leiser et al., 2008). Greater psychological distance tends to shift focus toward the abstract and holistic features of a situation, where moral principles exert a stronger influence (Grolleau et al., 2023).

Employing an intermediary to execute an astroturf tactic—such as fabricating grassroots movements or misrepresenting environmental claims—can be seen as an effort to
distance the company from the wrongdoing and potentially deny involvement. This use of an
intermediary, particularly through public relations entities (Beder, 1998), may be perceived as
an act of moral disengagement (Bandura, 1999). Such disengagement, which involves a
perceived attempt to avoid accountability, could backfire by eliciting stronger punitive
responses.

In summary, behavioural economics suggests that wrongdoing mediated through intermediaries is often judged more harshly due to factors such as increased psychological distance, heightened perceived intentionality, and efforts to obscure responsibility. Based on this reasoning, we hypothesize that indirect astroturfing (performed through an intermediary) will lead observers to judge it as more immoral and to recommend stricter punishment compared to astroturfing conducted directly by the company. Specifically, we formulate the following hypotheses:

H1: People judge indirect green astroturfing as more immoral than direct one.

H2: People express a higher willingness to punish indirect green astroturfing than direct one.

H3: People recommend more severe punishments for indirect green astroturf than direct one.

**4. Experimental survey**

We designed an exploratory survey experiment to gather initial evidence on our hypotheses.
Given our focus on how lay observers morally judge direct versus indirect astroturfing, this
method is particularly appropriate for identifying patterns and testing causal relationships in a
simple scenario (Weber, 1992; Robertson, 1993). By randomly assigning participants to
conditions involving either direct company deception or the use of a paid intermediary, we
can assess whether the same green astroturfing tactic is judged differently in terms of moral
seriousness and punishment deservingness.
Survey experiments allow for the controlled presentation of hypothetical business scenarios and standardized measurement of participant responses (Mutz and Kim, 2020). This design enables the isolation of key variables affecting moral evaluation, while randomization supports valid causal inference. In such settings, the emphasis is placed more on internal validity through random assignment than on external validity and population representativeness—especially when the goal is to determine whether a treatment has an effect, rather than to generalize its magnitude to the broader population.

## 4.1. Participants and design

We solicited 362 individuals in France (64% female, $M_{Age} = 37.8$ years) to participate voluntarily and anonymously in an online survey experiment (see Appendix A1), without monetary compensation.<fnref n="3" /> This convenience sample included family members, friends, students, and acquaintances, who were sent an e-mail requesting them to take part in the survey by clicking on a provided link. Some socio-demographic characteristics of our sample are presented in Table 1.

[Insert Table 1 around here]

Despite some critics, several scholars argued that convenience samples can provide reliable data (e.g., Mullinix et al. 2015; Coppock, 2017; see also Kelly et al., 2017). In addition, while we cannot completely rule out a potential researcher bias, this would likely affect all groups equally, as participants were randomly assigned to treatment groups and were unaware of the experiment's goal. Consequently, the observed differences between treatment groups are unlikely to be significantly influenced by this bias (see, e.g., Clot et al., 2022, for a similar argument). Using a non-representative sample can be surprising but is not inherently problematic when the research is exploratory and primarily focused on internal

<footnote n="3">³ To detect a medium effect size, assuming $\alpha = .05$ and $1 - \beta = .95$, the minimum required sample using the G*Power software (Faul et al., 2007) was 105 participants per treatment.</footnote>
validity—that is, testing causal relationships under controlled conditions—rather than external validity, or generalizability. Consequently, we caution readers against over-interpreting or over-generalizing our findings without first testing their robustness using a more representative sample.

We used a realistic and simple scenario<fnref n="4" /> where fake consumers and environmentalists posted reviews promoting the greenness of a company’s products (Weber, 1992). Participants read a scenario describing a detergent manufacturer that designed a computer program to post fake reviews from consumers and environmentalists on social media to promote its environmentally harmful products. The main part of the scenario is depicted below:

> *The PROPNET company manufactures detergents that are particularly harmful to the environment. [T0: It designed] [T1: It paid a specialist company to design] a computer program that posts fake reviews from consumers and environmentalists on social media. These reviews are always favourable to the company's products, presenting them as low-polluting while criticizing the products of competing companies.*

After the disclosure of this dishonest practice, participants were invited to (i) judge the morality of the corporate action on a Likert scale ranging from 1 (completely moral) to 7 (completely immoral), (ii) indicate whether the company deserves a fine, and if so, (iii) its amount up to €10,000, with €1,000 increments. We used a between-subjects design with random assignment of participants to the two treatments that only differ by whether the company posts fake reviews (T0) or through a paid intermediary (T1). Participants judged the

<footnote n="4">⁴ Interestingly, Kahneman and Tversky (1979, p. 265) defended the use of simple hypothetical situations, stating that “by default, the method of hypothetical choices emerges as the simplest procedure by which a large number of theoretical questions can be investigated.” Kahneman (2003, p. 723) even advocated for “doing psychology with single questions.”</footnote>
same company. Everything was made to keep the experimental manipulation to a minimal
level. Consequently, our test can be considered a conservative one.

## 4.2. Results

The mean responses for morality, punishment deservingness, and fine amount per treatment are presented in Table 2. While the levels of moral judgment and punishment are close to the upper limits both when the ‘dirty work’ is performed directly and through an intermediary, our results regarding the difference between direct and indirect astroturfing are mixed. On one hand, there is no significant difference for morality (ttest; *p*=0.58), suggesting that H1 is not supported. We speculate that most participants were so outraged by the company manipulation that the distancing effect became very secondary. On the other hand, however, punishment deservingness is significantly higher when the company outsources astroturfing, compared to direct astroturfing (ttest; *p*=0.03), suggesting that H2 is supported. Moreover, the recommended punishment is significantly more severe (an average fine of €8,151) when the company outsources astroturfing compared to the punishment associated with direct astroturfing (an average fine of € 7,617) (ttest; *p*=0.07), thus supporting H3.

[Insert Table 2 around here]

Moreover, we run a multivariate linear regression to control for individuals’ characteristics (Table 3). The results remain robust. We found that the outsourcing variable is significant only regarding the punishment deservingness and fine amount. However, while the results suggest that usual socio-demographic variables are poor predictors of moral judgment or recommended punishment in the case of astroturfing arrangements, we cannot draw clear-cut conclusions regarding these control variables.

[Insert Table 3 around here]

## 4.3. Discussion
Green astroturfing exploits strategically human biases and heuristics to promote vested
interests under the guise of representing grassroots movements. In both treatments,
participants rated green astroturfing as highly immoral—near the upper limit of our scale—
and recommended severe punishment. This finding could seem somewhat natural, but it is
reassuring about public opinion, especially in a post-truth world saturated with fake news and
“alternative facts” (Chan, 2024; Effron and Helgason, 2022).

An indirect arrangement allows the organization to distance itself from the astroturfing
operation and may seem attractive from a legal perspective. Indeed, from the corporation’s
viewpoint, using an intermediary enables it to reap the benefits of fake reviews while avoiding
some of its pitfalls. Nevertheless, the obvious intention to mislead, once disclosed, generates a
more severe punishment recommendation that could cancel the indirect arrangement
advantages (see Farrell and Schneier, 2021). Our results extend Effron and Helgason’s (2022;
see also Effron et al., 2018) work by showing how organizational hypocrisy (through
intermediaries) triggers even stronger condemnation than direct deception, and align with
Jauernig et al.’s (2021) framework, revealing that punishment severity increases with
deception complexity. Corporations should remain cautious not to be victims of short-termism
by overweighting the possible benefits of astroturf tactics and downsizing its considerable
detrimental effects (Yin et al., 2025).

These findings contribute to ongoing discussions in business ethics and persuasion
research by empirically demonstrating the psychological and moral dimensions of green
astroturfing. Specifically, we build on concerns around corporate manipulation of public
opinion by showing that individuals do not judge all green astroturfing equally—outsourcing
the deception intensifies moral condemnation and punishment recommendations. This nuance
advances the discourse on moral attribution in corporate contexts and underscores the ethical
risks of indirect influence strategies. Our work also highlights how basic cognitive heuristics
can be systematically exploited, adding to broader debates on the psychological
vulnerabilities leveraged in corporate environmental messaging.

Beyond its detrimental effects on the involved agents, astroturfing generates consequences that can affect the whole economy and lead to general suspicion over all green endeavours, even the most honest ones (Gino et al., 2009). As a consequence, some companies may even opt for “green blushing” or “green hushing” that will dampen green progress (Falchi et al., 2022). Green non-governmental organizations are also collateral victims of green astroturfing, which is likely to slow down environmental progress by eroding people’s trust in legitimate environmental advocacy and demobilizing individuals who would otherwise actively support environmental initiatives. Given that an ambitious climate policy requires strong public support, astroturfing in all its forms harms this foundation. Indeed, by undermining public trust even in usually trustworthy entities such as environmental NGOs, citizen movements, and scientists (Walker and Le, 2023), astroturfing can affect many dimensions of a green transition (e.g., engagement in green initiatives, policy support) and delay the adoption of changes necessary to address climate change and environmental challenges.

The ethical and legal implications of astroturfing are significant and merit further discussion. There is a fundamental ethical obligation for organizations to disclose their interests when promoting messages (see Healy and Palepu, 2001 about the underlying logic).

Astroturfing often involves presenting false, selective or partial information to sway public opinion toward corporate goals. Such practices risk eroding public trust, not only in the organizations involved but also in broader institutions and media platforms (Kang et al., 2016). Who is responsible when astroturfing campaigns lead to misinformation or harmful policies? Establishing accountability is crucial in addressing the potential negative consequences of these practices (Leiser, 2016). Companies should consider the long-term impacts of engaging in astroturfing tactics on their reputation and consumer trust. Deceptive
tactics like astroturfing can have profound psychological and behavioural effects on
consumers (see, e.g., Darke and Ritchie, 2007). The subsequent heightened scepticism can
persist, complicating future attempts at persuasion, even by ethical and transparent
advertisers. Ethical marketing practices should prioritize honesty and transparency over
manipulative strategies.

The potential legal and social repercussions of astroturfing can become crucial. In
some jurisdictions, deceptive advertising practices can lead to legal action against companies.
Regulatory bodies are increasingly scrutinizing misleading marketing tactics, including
astroturfing (Scott, 2019). Interestingly, research on countering astroturfing and other forms
of misleading information is rapidly expanding (Roozenbeek et al., 2023). The erosion of trust
in public discourse can have far-reaching effects on democracy and civic engagement. When
citizens feel manipulated by hidden agendas, it can lead to negative spillover effects, apathy,
or cynicism towards political processes, well beyond the considered astroturfing initiative
(Walker and Le, 2023).

**5. Conclusion**

The proliferation of astroturfing represents a critical challenge for market integrity and
consumer trust in the digital age. Online environments and artificial intelligence (AI)-based
tools have largely amplified the capacity of astroturfers to orchestrate harmful activities on
unprecedented scale and sophistication. Various arrangements are possible, but some basic
elements remain the same. In the case of astroturfing, the deception lies more in the source
(faking a genuine grassroots movement) and validation (bandwagon effect) of what is
communicated. This persuasion tactic exploits human biases (e.g., in-group bias, multiple
source bias, illusory truth effect) to convey misleading information and influence public
debate.
Using an experimental survey, we did not find evidence that indirect astroturfing is judged more severely than direct astroturfing, from a moral viewpoint. However, the punishment deservingness and level are significantly higher when the company outsourced the astroturfing operation. This result suggests that once astroturfing is disclosed, the public is unlikely to be apathetic and can seek ways to punish manipulative companies, especially if they use intermediaries to perform this manipulation. These strong negative reactions can be considered good news, especially in a post-truth world, and can push would-be astroturfers to think twice before engaging in this way.

While previous research has examined deceptive political and corporate practices, our findings uniquely highlight how artificial distance, introduced through the use of an intermediary, influences moral judgment of the deceptive act. Indeed, many entities employ public relations firms or similar intermediaries to carry out their astroturfing initiatives. At the same time, our scenario was somewhat basic, given that astroturfing spans a continuum— from amplifying existing grassroots voices (often exaggerating their significance) to manufacturing entirely fake grassroots movements *ex nihilo*. Astroturfing employs a broad and continually evolving set of techniques, making such arrangements harder to detect and reducing the risk of identifying the true initiators.

Our exploratory survey experiment is just a first step and more research is needed. Our convenience sample constitutes a possible limitation. Conducting similar studies among other samples, notably representative ones, and refining our questionnaire, would strengthen our findings. Other dimensions can be explored, such as whether the creativity of the astroturfing tactic influences its perceived unethicality, the ‘size of the lie’ (i.e., does the size of the lie make astroturfing more or less morally acceptable?), spillover effects, and the behavioural consequences of (repeated) astroturfing. Moreover, despite the difficulty of gathering data on astroturfing operations, an incentive-compatible experiment could enlighten some dimensions, such as the citizens’ or consumers’ willingness to pay to detect astroturf.
The rise of astroturfing activities in various domains could lead individuals to suspect information and sources, well beyond those communicated by imposters. Astroturfing could spill over and threaten non-implied organizations. The whole sustainable movement can be harmed (see, e.g., Walker and Le, 2023). This collective toll could trigger a kind of (preventive) self-policing. Moreover, it seems crucial to develop tactics allowing for spotting astroturfing at an early stage and reducing its attractiveness through well-crafted public and private regulations, which is difficult (Chan, 2024). Journalistic fact-checks on the authenticity of support can serve as a crucial first step in combating astroturfing. Inoculation-based strategy seems promising to develop public ability to cultivate psychological reactance toward called astroturf, ultimately making this unethical public relations attack less persuasive (Boman, 2023). Training targets or watchdog groups to detect astroturf-related language and clues (e.g., euphemisms, attacks on individuals, emotion-based content rather than fact-based content), developing smart applications, informing and possibly debiasing people regarding the exploitation of their biases, educating and training consumers, naming, punishing and publicly shaming initiators could constitute potential avenues. However, developing comprehensive detection systems remains challenging due to the inherent complexity of distinguishing authentic grassroots content from sophisticated astroturfing operations, particularly given the structural diversity and evolving nature of deceptive practices (Mahbub et al., 2019). These initiatives could feed ‘cat and mouse games’, where astroturfers will attempt to game the improved system (Farrell and Schneier, 2021).
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Box 1. Examples of astroturfing

<table><thead><tr><td>Sponsor and source</td><td>Country and year</td><td>Description of the astroturfing tactic</td></tr></thead><tbody><tr><td>Walmart (Bindu Kota, 2010)</td><td>United States (2005)</td><td>Working Families for Walmart appears as a spontaneous grassroots group and praises the efforts made by Walmart for the welfare of its employees. In reality, the group is supported financially by Walmart through a public relations company, Edelman (see also the blog: Wal-Marting Across America).</td></tr><tr><td>McDonald's (Bindu Kota, 2010)</td><td>Japan (2008)</td><td>1,000 people queuing outside the fast food major's outlet in Kansai from midnight onwards. In reality, McDonald's paid 1,000 part-time employees $11 an hour each to queue up and reimbursed their burger purchase.</td></tr><tr><td>Monsanto (Lombart, 2019)</td><td>France, UK, Spain, Italy, etc. (2018)</td><td>Spontaneous groups of farmers campaigning in favour of glyphosate. In reality, the real names of several farmers were used without their agreement to constitute fake supporting groups with misleading and euphemistic denominations (e.g., Agriculteurs et Liberté, Free to Farm) in favour of the Monsanto herbicide.</td></tr><tr><td>Western Fuel Association (Exxon Secrets, 2006)</td><td>United States</td><td>Greening Earth Society was a misleading grassroots organization that minimized climate change issues.</td></tr><tr><td>Companies with commercial interest in shale gas development (Lits, 2021)</td><td>European Union</td><td>Responsible Energy Citizens Coalition is a misleading front group promoting the development of shale gas and presenting it as environmentally friendly.</td></tr><tr><td>Pro-oil groups and campaigns backed by governments (Kinder, 2024)</td><td>Canada</td><td>Using social media to mask orchestrated, corporate- and- state-funded pro-oil messaging as grassroots support, reposted via networks like Canada Action and Energy Citizens to manufacture consent and reshape public opinion</td></tr></tbody></table>
<table><caption>Table 1. Participants' socio-demographic characteristics (N=362)</caption><thead><tr><th></th><th></th><th>Mean</th><th>Std. Dev.</th></tr></thead><tbody><tr><td>Age (continuous)</td><td></td><td>37.864</td><td>14.819</td></tr><tr><td>Gender (=1 if Female)</td><td></td><td>0.646</td><td>0.478</td></tr><tr><td rowspan="4">Education</td><td>Cat. 1 (French baccalaureate or less)</td><td>0.135</td><td>0.342</td></tr><tr><td>Cat. 2 (1 to 3 university years)</td><td>0.472</td><td>0.499</td></tr><tr><td>Cat. 3 (4 university years or more)</td><td>0.392</td><td>0.488</td></tr><tr><td>Cat. 1 (1000€/month or less)</td><td>0.229</td><td>0.420</td></tr><tr><td rowspan="2">Earnings</td><td>Cat. 2 (1001€ to 2000€/month)</td><td>0.480</td><td>0.500</td></tr><tr><td>Cat. 3 (more than 2000€/month)</td><td>0.287</td><td>0.453</td></tr></tbody></table>
<table><caption>Table 2. Mean responses for morality, punishment deservingness, and fine amount</caption><thead><tr><th></th><th>Treatment T0 (direct; N=183)</th><th>Treatment T1 (indirect; N=179)</th></tr></thead><tbody><tr><td>Morality</td><td>6.710</td><td>6.759<sup>(ns)</sup></td></tr><tr><td>Punishment deservingness (%)</td><td>95</td><td>99<sup>(**)</sup></td></tr><tr><td>Fine amount (€)</td><td>7617.486</td><td>8150.838<sup>(*)</sup></td></tr></tbody></table>

(**), (*): significance at the 5% and 10% levels of a t-test comparing both treatments. (ns): not significant.
<table><caption>Table 3. Multivariate linear regression of the effect of indirect astroturfing</caption><thead><tr><th></th><th></th><th>Perceived morality</th><th>Punishment<br>deservingness</th><th>Fine amount</th></tr></thead><tbody><tr><td>Indirect astroturfing</td><td></td><td>0.074</td><td>0.043**</td><td>642.047**</td></tr><tr><td>Age (continuous)</td><td></td><td>-0.001</td><td>0.000</td><td>6.581</td></tr><tr><td>Gender (=1 if female)</td><td></td><td>0.142</td><td>0.018</td><td>22.939</td></tr><tr><td rowspan="3">Education</td><td>Cat. 1 (Ref)</td><td>-</td><td>-</td><td>-</td></tr><tr><td>Cat. 2</td><td>-0.249**</td><td>-0.045</td><td>-693.556</td></tr><tr><td>Cat. 3</td><td>-0.096</td><td>-0.021</td><td>-695.038</td></tr><tr><td rowspan="3">Earnings</td><td>Cat. 1 (Ref)</td><td>-</td><td>-</td><td>-</td></tr><tr><td>Cat. 2</td><td>0.269**</td><td>-0.008</td><td>594.415</td></tr><tr><td>Cat. 3</td><td>0.185</td><td>-0.002</td><td>1456.194***</td></tr><tr><td>Constant</td><td></td><td>6.638***</td><td>0.952***</td><td>7195.897***</td></tr><tr><td>Observations</td><td></td><td>362</td><td>362</td><td>362</td></tr><tr><td>F</td><td></td><td>1.41</td><td>1.29</td><td>3.05***</td></tr><tr><td>R2</td><td></td><td>0.0272</td><td>0.0250</td><td>0.0250</td></tr><tr><td colspan="5" style="text-align: center;">Multivariate test, F</td></tr><tr><td>Wilks' lambda</td><td></td><td></td><td>0.8985**</td><td></td></tr><tr><td>Pillai's trace</td><td></td><td></td><td>0.1046**</td><td></td></tr></tbody></table>

For Education, categories 1 to 3 correspond, respectively, to French baccalaureate or less, 1 to 3 university years, and 4 university years or more. Earnings categories 1 to 3 correspond to 1000€/month or less, 1001€ to 2000€/month, and more than 2000€/month, respectively. *** and ** indicate significance at the 1% and 5% levels respectively.
# Appendix A1. Survey translation

(There is no right or wrong answer. The name and scenario described below are hypothetical. Please read the scenario attentively. We are only interested in your honest opinion)

## [Direct astroturfing treatment]

A. The PROPNET company manufactures detergents that are particularly harmful to the environment. It designed a computer program that posts fake reviews from consumers and environmentalists on social media. These reviews are always favourable to the company's products, presenting them as low-polluting while criticizing the products of competing companies.

## [Indirect astroturfing treatment]

A. The PROPNET company manufactures detergents that are particularly harmful to the environment. It paid a specialist company to design a computer program that posts fake reviews from consumers and environmentalists on social media. These reviews are always favourable to the company's products, presenting them as low-polluting while criticizing the products of competing companies.

Please rate the moral character of PROPNET's behaviour on the scale below from 1 (completely moral) to 7 (completely immoral) by circling the corresponding number:

<table><tr><td>1<br>Completely moral</td><td>2</td><td>3</td><td>4</td><td>5</td><td>6</td><td>7<br>Completely immoral</td></tr></table>

B. In your opinion, should this behaviour be punished by a fine? Yes ☐ No ☐

If you answer “yes”, what is the amount of the fine that you recommend among the following choices (please circle the amount which is the closest to your choice)?

<table><tr><td>1000 €</td><td>2000 €</td><td>3000 €</td><td>4000 €</td><td>5000 €</td><td>6000 €</td><td>7000 €</td><td>8000 €</td><td>9000 €</td><td>10000 €</td></tr></table>

C. Please indicate the following information:

<table><tr><td>1. Age: ________ years</td><td></td></tr><tr><td>2. Education: Bac or less ☐ Bac + ________ years ☐</td><td></td></tr><tr><td>3. Gender: M. ☐ F. ☐</td><td></td></tr></table>

4. Your net monthly income:

a) Less than 1000€ ☐

b) Between 1 000€ and 2 000€ ☐

c) More than 2 000€ ☐