Why Bias-Free AI Is a Myth
Designing Governed Systems for Human-Centric Intelligence
A comprehensive analysis of how bias permeates AI systems at every stage—from data collection through human interaction—and governance strategies for building accountable, human-centric AI.
Why Bias-Free AI Is a Myth: Designing Governed Systems for Human-Centric Intelligence
Introduction: Framing the Myth of Neutrality
There is a persistent myth that AI systems are inherently objective because they rely on "data-driven" reasoning. In reality, AI reflects human decisions at every turn – in what data are collected, how models are built, and where they are applied. For example, in healthcare AI, training data often omit marginalized groups, so models trained on city hospital data systematically underdiagnose rural or minority patients. [1] The well-known Obermeyer et al. study illustrates this: a risk algorithm using medical costs as a proxy for health need systematically underestimated Black patients' illness because they historically received less care, so at equal risk scores Black patients were sicker than White patients. [11] These real-world examples show that AI systems "are only as effective as the data and assumptions under which they are created". [2] In short, AI is a human artifact – its data, objectives, and evaluation metrics carry human biases, so "the myth of neutrality" obscures the fact that AI inevitably embeds human context. [14] Therefore, rather than aiming for impossible "bias-free" AI, we must design governance that makes bias explicit, measurable, and controllable.
Human Bias: Sources and Types
Bias enters the AI pipeline first through people. Human cognition and society contain many systematic distortions, which then seep into data and models. Key sources include:
Cognitive bias: People rely on heuristics (e.g. framing effects, recency/primacy) that skew judgment. Studies show that even LLM-generated content can induce these biases in readers. For instance, LLM summaries change sentiment in about 22% of cases and cause "primacy" effects in 6%, leading to different user decisions. (One experiment found humans were 32% more likely to buy a product after reading an LLM-generated summary than the original review.) [5]
Cultural bias: The dominant narratives of society are over-represented in text data. Training corpora often reflect the language and norms of majority groups or high-resource settings, marginalizing minority viewpoints. For example, public health data drawn from high-income regions omit many cultural and linguistic variations, so models fail when applied in low-resource settings. [1] This skews outputs toward the perspectives of whoever created or controls the data.
Social identity bias: Language carries stereotypes tied to race, gender, religion, etc. LLMs trained on large text collections inherit these associations. Hu et al. find that almost every modern language model shows ingroup favoritism and outgroup derogation – e.g. completing sentences like "We are X" in ways that favor the model's own group. [6]
Annotator (label) bias: Even human labelers introduce bias. Crowdworkers' own perspectives and heuristics color their annotations, which then become "ground truth" for models. As Gautam and Srinath note, "biases present in the label data can induce biases in the trained models". In practice, non-representative annotator pools or simplistic annotation tasks can embed stereotypes or misunderstandings into training data. [2]
In sum, datasets are not neutral mirrors of reality. They reflect power, access, and historical inequalities. More data or larger models do not magically erase these biases – they may amplify them. As Joseph et al. remark for public health, relying on flawed data can "widen existing health gaps" rather than close them. [1] Recognizing these human-origin biases is crucial: they cascade through the AI lifecycle, and no purely technical fix at the model layer will eliminate what comes from society.
Bias in LLM Training: Pretraining and Fine-Tuning
Pretraining: Statistical and Representational Bias
During pretraining, LLMs absorb correlations from text. If certain identities are statistically linked to roles or traits in the data, the model internalizes that skew. For example, gender pronouns in text often co-occur with gender-stereotypical occupations. Zhao et al. found that standard coreference systems (used to link "he" or "she" to named entities) achieved much higher accuracy when the referent matched gender stereotypes (e.g. "the nurse"–female) than when it violated them. [7] In other words, the model "prefers" pro-stereotypical associations. Similarly, language models exhibit broad social identity biases: Hu et al. show that prompted to write about their own group vs. another ("We are Democrats; we are Republicans" etc.), almost all models amplify in-group positivity and out-group negativity, mirroring human social bias. [6] These are not bugs but logical outcomes of statistical learning on biased corpora. Importantly, simply scaling up model size does not inherently neutralize these patterns; targeted interventions (e.g. balanced data, debiasing algorithms) are needed to counteract them. [2]
Fine-Tuning and Alignment: Suppression is not Removal
Instruction fine-tuning and RLHF (reinforcement learning from human feedback) can reduce overtly toxic or offensive completions under normal prompts. However, this tuning does not erase the model's latent associations. In fact, adversarial research shows that alignment safeguards are brittle. By engaging the model in multi-turn "persuasive" dialogue, attackers can manipulate it around its filters. Zeng et al. developed social-engineering prompts (Persuasive Adversarial Prompts) that coerced models into policy-violating outputs with over 92% success. [3] Similarly, Liu and Lin's "psychological manipulation" approach (HPM) repeatedly exploits the model's drive for consistent, human-like dialogue to override safety constraints, achieving an 88.1% attack rate. [4] These results indicate that fine-tuning shapes surface behavior only under normal conditions; deep-seated biases and weaknesses remain. Thus, we conclude alignment is not a one-time neutralization of bias, but an ongoing challenge of interactive security.
Emergence of Agentic Bias: When LLMs Begin Making Decisions
Bias Amplification through Interaction and Dynamics
When LLMs act as agents (e.g. chatbots, decision tools, or multi-LLM systems), bias becomes a system-level phenomenon. Ashery et al. demonstrate this with simulated LLM populations: even if individual agents hold no bias, groups of agents negotiating a shared language or convention can spontaneously develop collective prejudices. [8] A few biased "leaders" can sway the whole group's norms. In practical terms, deploying many AI agents in a workflow (for routing cases, coordinating tasks, etc.) can create feedback loops that amplify small initial skews. Bias is no longer just "in the model" but a property of the entire socio-technical system and its dynamics.
Human Conformity Effects in Human–AI Teaming
LLM bias does not stay inside the machine – it leaks into human decision-making. In collaborative settings, biased AI advice strongly influences people. Wilson et al. ran resume-screening experiments where participants saw LLM recommendations that favored one demographic group. [9] Even when participants thought the AI was low-quality, human hiring choices shifted dramatically in the biased direction. Specifically, participants chose the AI-favored group up to 90% of the time when the recommendation was strong. (Without AI, selections were equal across groups.) This conformity effect can nullify human autonomy: users trust or follow AI advice even if they know it is flawed. Such human–AI coupling means that model bias propagates into real-world outcomes: biased AI leads organizations to make biased decisions. Hence governance must consider not only algorithmic fairness, but how AI shapes human behavior.
Reactance and Autonomy: Mapping Psychological Reactance to LLM Behavior
Psychological reactance refers to humans resisting perceived limits on their freedom. Analogously, interactions with AI can trigger counterproductive behaviors. LLMs have no intentions, but they respond to conversational cues. Recent studies frame model jailbreaks as forms of social manipulation. Zeng et al. build a taxonomy of persuasive strategies (e.g. guilt, reciprocity) and show that by "humanizing" prompts, non-expert users can reliably trick LLMs into breaking rules. [3] Liu & Lin further illustrate that chaining conversation turns to exploit a model's desire for consistency can systematically overturn its safety checks. [4] These findings suggest alignment is as much about interaction security as about filtering: social-engineering attacks can work like effective adversarial hacks. In practice, this means developers must monitor not only single-turn prompts but also the full dialogue state for signs of persuasion attacks, treating alignment as an ongoing dialogue challenge.
Case Studies: Bias Manifestation in Decision Agents
Healthcare Decision Support
Studies comparing AI and human recommendations in medicine expose notable disparities. In one vignette-based study, Kim et al. found that AI chatbots gave different treatment suggestions depending on patient race, gender, or socioeconomic status, even though medical guidelines should not vary by these attributes. [10] These AI biases paralleled known clinician biases, underscoring that AI can inherit systemic inequities. In another case, Obermeyer et al. showed that a widely-used health-risk algorithm (for managing populations) systematically under-identified Black patients' needs because it used healthcare cost as a proxy: at the same risk score, Black patients were in worse health than White patients. [11] This "proxy bias" arose from the data reflecting historical access disparities. Both examples highlight different mechanisms: (i) LLM/agent bias in controlled prompts; (ii) structural proxy bias in deployed systems. Together they show healthcare AI can encode and even exacerbate inequities.
Hiring and Employment Pipelines
Bias in automated hiring is a classic concern. Earlier AI screening tools (e.g. Amazon's 2018 resume filter) famously discriminated against women. Today's LLM-based tools carry similar risks, amplified by human–AI effects. As noted, when biased recommendations are introduced, human recruiters tend to follow them. This means even subtle model biases can sway hiring decisions at scale. Controlled experiments confirm this: LLMs primed to rate candidates by gender or race cause real evaluators to become more discriminatory, aligning with the AI's bias. In sum, human–AI coupling in hiring can undermine autonomy, making bias an organizational, not just technical, problem. [9]
Technical Governance: Mitigation Tools, Guardrails, and Architectural Patterns
Audit and Evaluation
Bias must be measured before it can be managed. Audits should go beyond aggregated accuracy to examine outcomes for subgroups and for controlled scenarios. One approach is counterfactual testing: evaluate the system on matched inputs that differ only in a protected attribute. For example, Lin and Li introduce a paired-evaluation framework that holds task content fixed while swapping demographic details, isolating identity effects on model responses. Such tests can reveal differences in language tone, confidence, or advice across groups even when overall scores are similar. Audits should also include stratified evaluation (performance metrics broken down by subgroup) and workflow impact analysis to see how AI outputs affect decisions. Importantly, domain-specific tests are needed: an audit for a Japanese-language LLM should check culturally relevant stereotypes. For instance, Nakanishi et al. found that a Japanese-native LLM gave more toxic, less cautious responses to certain stereotype-triggering prompts than equivalent English or Chinese models. [12] This highlights that bias triggers and norms vary by context; global deployments require localized audit criteria. Finally, keep audit tooling public and continuous: incorporate new metrics (e.g. sentiment, politeness, confidence) and use red-teaming to simulate malicious or manipulative inputs.
Defense Against Persuasion and Jailbreak Dynamics
Given the demonstrated success of social-engineering attacks, governance must treat LLM alignment as a security challenge. This means active red-teaming for multi-turn jailbreaks using the latest tactics. Defense-in-depth is crucial: rely on multiple safeguards, not just a single refusal rule. Technical work like Zhang and Sun's Differentiated Directional Intervention shows that sophisticated, layered attacks can neutralize a model's content filter (achieving up to ~97.9% attack success on Llama-2). [13] We should monitor such research as threat intelligence. Practically, it is wise to include runtime monitoring of conversation state, rate-limit chains of prompts, and even query the model's own "confidence" or uncertainty. Any anomalous sequence of requests or unexpected compliance should raise alerts. In short, anticipate adversarial manipulations as part of the threat model, and build layered response strategies (e.g. fallbacks, supervisor review) rather than hoping for an unbreakable single filter. [3], [4], [13]
Sociotechnical Governance and Accountability
Technical fixes alone cannot eliminate bias. As Selbst et al. emphasize, focusing only on abstract models risks missing where real harms occur. [14] Fairness should be engineered in context, linking model behavior to actual social outcomes. Practical steps include: clearly document decision rights (who is accountable for an AI output), maintain trace logs of high-impact decisions for auditing, and enforce human oversight that can meaningfully intervene. This means designing workflows so that humans do not merely rubber-stamp AI suggestions, but can question or override them. Institutions should build escalation paths (e.g. ethics review boards) for when AI-driven decisions are challenged. Accountability mechanisms (like impact assessments, public reporting of bias metrics) help ensure that models serve their intended populations responsibly. In sum, a sociotechnical approach ties the AI to governance processes – avoiding the trap of treating fairness as a "modular" afterthought. [14]
Recommendations for Decision Makers: Procurement, Oversight, Deployment
Demand Transparency: Require vendors to provide documentation of training data sources, known limitations, and evaluation results by subgroup. This includes model cards or similar disclosures that enumerate biases discovered in testing. [2]
Institutionalize Bias Audits: Set up regular third-party audits (not just one-off tests) that use methods like counterfactual swapping and stratified performance checks. Audits should cover both the model and how it's used in workflow. [2], [14]
Design for Human Override: In high-stakes settings (health, hiring, credit, etc.), ensure "automation is opt-in" rather than default. Implement supervisory gates and clear escalation policies so that uncertain or sensitive cases are reviewed by experts. Avoid full automation without checks. [14]
Monitor Human–AI Coupling Effects: Beyond auditing the model alone, study how AI suggestions actually change human decisions. For example, in hiring tools, measure whether interviewers' selections shift toward AI recommendations (as shown by Wilson et al.). [9] Adjust training or interface design if undue conformity is observed.
Treat Jailbreaks as Security Threats: Continuously simulate adversarial "persuasion" attacks (e.g. red-team dialogues) and update defenses accordingly. Keep abreast of emerging jailbreak methods (e.g. psychological attacks, directional activation exploits) and treat them as vectors like malware. Ensure monitoring for unusual query patterns or overly compliant model behavior at runtime. [3], [4], [13]
By combining these strategies—technical safeguards with institutional checks and human oversight—organizations can build bounded, bias-aware AI systems. The goal is not impossible neutrality, but accountable AI: systems designed to surface, measure, and manage bias, with clear responsibility and recourse when things go wrong.
Conclusion: Toward Bounded, Bias-Aware AI Systems
Bias-free AI is a myth because bias is woven through society, data, models, and people. Evidence abounds: LLMs reflect social identity prejudices, AI chatbots in medicine give systematically different advice by race and gender, and deployed algorithms can encode structural inequities (e.g. underestimating Black patients' needs). [6], [10], [11] Moreover, biased models reshape human behavior, as people tend to conform to the AI's direction. [9] Even alignment techniques aren't foolproof: sophisticated multi-turn attacks can coerce models into unsafe outputs. [3], [4], [13] The takeaway is that bias isn't a simple bug to fix post hoc; it's a complex socio-technical phenomenon. [14]
Effective governance is therefore the aim. Organizations should stop treating fairness as a "model tuning" detail and instead address it as an engineering, operational, and policy challenge. [14] AI systems must be designed for human-centric outcomes, with checks at every layer: from diverse data collection to rigorous multi-faceted auditing, from adaptive interfaces to accountable oversight. Only by making bias visible and controlled – rather than buried under the assumption of objectivity – can we build AI that serves equity and human values in practice. [14]
References (selected)
[1] J. Joseph et al., "Algorithmic Bias in Public Health AI: A Silent Threat to Equity in Low-Resource Settings," Front. Public Health, 2025.
[2] S. Barocas, M. Hardt, A. Narayanan, Fairness and Machine Learning: Limitations and Opportunities, MIT Press, 2023.
[3] Y. Zeng et al., "How Johnny Can Persuade LLMs to Jailbreak Them…," Proc. ACL, 2024.
[4] Z. Liu, X. Lin, "Breaking Minds, Breaking Systems: Jailbreaking LLMs via Psychological Manipulation," arXiv 2512.18244, 2025.
[5] A. Alessa et al., "Quantifying Cognitive Bias Induction in LLM-Generated Content," arXiv 2507.03194, 2025.
[6] T. Hu et al., "Generative Language Models Exhibit Social Identity Biases," Nat. Comput. Sci., 2025.
[7] J. Zhao et al., "Gender Bias in Coreference Resolution…," NAACL 2018.
[8] A. Ashery et al., "Emergent Social Conventions and Collective Bias in LLM Populations," Sci. Adv. 2025.
[9] K. Wilson et al., "No Thoughts Just AI: Biased LLM Recommendations Limit Human Agency…" arXiv 2509.04404, 2025.
[10] J. Kim et al., "Assessing Biases in Medical Decisions via Clinician and AI Chatbot Responses…," JAMA Netw. Open, 2023.
[11] Z. Obermeyer et al., "Dissecting Racial Bias in an Algorithm…" Science, 2019.
[12] A. Nakanishi et al., "Analyzing the Safety of Japanese LLMs in Stereotype Prompts," arXiv 2503.01947, 2025.
[13] P. Zhang, P. Sun, "Differentiated Directional Intervention: A Framework for Evading LLM Safety," arXiv 2511.06852, 2025.
[14] A. D. Selbst et al., "Fairness and Abstraction in Sociotechnical Systems," Proc. FAccT, 2019.

