The Case You’ve Already Won (In Your Head)

New research on how decision-making processes silently inflate confidence—and ways to disrupt them

BY ANN T. MARSHALL

Every attorney has been there. A potential case from a client arrives that sounds promising. Each new detail seems to confirm the theory that is forming in your mind. Within weeks, you have done legal research, reviewed documents, spoken with witnesses, and drafted the initial letter to the other party. The case feels strong.

But is it? Or has something happened in that short time—something that has more to do with psychology than law?

Newly published research concludes that the very process of reaching a decision can produce confidence that is not warranted by the information. The phenomenon is called predecisional information distortion. And as lawyers routinely evaluate complex, ambiguous, and sequentially received information when committing to a theory of a case, this type of bias is particularly relevant.

What the Research Found

A study published in 2026 in Judgment and Decision Making¹1 Peter J. Boyle and Pete Nye, “Information Distortion as a Source of Overconfidence in Managerial Decisions,” Judgment and Decision Making (2026, vol. 21:e3). by researchers Peter J. Boyle of Central Washington University and Pete Nye of the University of Washington–Bothell examined how MBA students with business experience grew confidence during a decision-making task. 

In the study, subjects evaluated whether or not to launch an advertising campaign after receiving discrete pieces of information sequentially. Crucially, new information was carefully calibrated to be neutral—equally supportive of either decision.

The core finding: As subjects leaned toward one option after they received initial information, they unconsciously interpreted any further, neutral information as more supportive of that first option than it actually was. The effect was measurable: as subjects’ interpretations of information shifted toward a leading option, their confidence increased in tandem, with a statistically significant relationship between the two. And the more the subjects distorted the information, the more confident they became—confident in a choice that the received information did not clearly favor. The subjects were also unaware that anything was amiss. In the researchers’ words, the overconfidence “went undetected by decision makers, as they were unmindful of any bias they might have had to illegitimately inflate their confidence.” 

None of this required a predetermined preference of the participants, as they were asked to determine which option they preferred after initial information was given. The distortion developed organically, mid-decision, as a tentative preference emerged. 

Why Lawyers Should Take Notice

Consider how a litigator typically works through a case: a new matter arrives, the lawyer hears one side of the story, and documents arrive in batches. In this early phase, there is rarely an advocate for an opposing view. Over months of depositions, each development is assessed against an emerging client theory. At that point, the case is not just being evaluated—it is being constructed. By trial preparation, the lawyer has developed a confident working view built from the kind of sequential intake studied by Boyle and Nye. 

The distortion effect does not stem from bad faith or laziness. The goal of maintaining consistency—having each new piece of information fit what you already believe—operates below conscious thought. Even hard work, intelligence, and years of experience may not be reliable defenses; one small sample size in the study, though not conclusive, suggested no meaningful relationship between cognitive traits and susceptibility to distortion-driven overconfidence.

The research warns that if confidence builds too quickly, decision-makers might terminate their search for countervailing information and settle on a suboptimal choice. In a legal context, this “suboptimal choice” may be overstating the strength of a case, advising a client against a settlement, pursuing litigation that drains resources, or failing to prepare adequately for weaknesses that have been downplayed or even dismissed.

The Mechanics of the Bias

In the study, information purposefully designed to be neutral—equally supportive of either outcome—was pulled toward the emerging preference. The participants did not ignore contrary evidence outright; they subtly reweighted it through the lens of what they already believed.

Imagine reviewing a medical expert’s report in a personal injury matter. You have already concluded your client has a strong claim. The report is genuinely mixed. The distortion effect predicts you will perceive the supportive elements as more significant, and the complications as more equivocal, than an independent person would. Your confidence increases. You move forward.

The process is cumulative: Greater confidence leads to more distortion of the next piece of information, which leads to even greater confidence—a cycle that essentially “bootstraps” confidence over time, with each new piece of information adding fuel even when it isn’t warranted.

Mediation as a Correction Mechanism

If individual defenses against this bias are scarce, external structures may be more effective than internal ones. Here, the mediation process offers something uniquely valuable: a setting designed to interrupt the cycle the research describes.

The mediator introduces a genuinely neutral lens. Unlike a colleague who has lived the case alongside you, or a client whose investment reinforces your own, a skilled mediator has no commitment to the working theory you have built. Their job is to probe it—to ask questions, surface risks you may have minimized, and hold space for interpretations of the evidence your own process has been quietly suppressing. In the language of the research, the mediator disrupts the consistency goal—the cognitive tendency to make new information fit the emerging or existing theory. They introduce friction where the distortion effect thrives in its absence.

Mediation makes the other side’s position legible. One underappreciated feature of the mediation process is the moment when you are required to genuinely engage with the other party’s perspective. Not refute it, but hear it. Having a dialogue with a neutral party about an opposing position is easier because it eliminates another bias that gets in the way: reactive devaluation, the cognitive tendency to undervalue concessions because they are offered by an adversary. For many attorneys, mediation is the first time the other side’s narrative has been presented outside their own adversarial frame. It is harder to sustain a distorted interpretation of information when you are sitting with someone whose equally confident and opposing interpretation is being articulated clearly by a neutral party.

The mediator can name what the parties cannot. When all sides arrive certain they will prevail, an experienced mediator’s role is in part to surface that irreconcilability without assigning blame. Helping parties recognize that their respective certainties may have been shaped by the same predictable process, rather than by an objective difference in the quality of their evidence, can move a stalled negotiation in ways that a legal argument cannot.

Early mediation interrupts the cycle before it cements. The research shows that distortion builds as information accumulates and confidence hardens. The earlier in a dispute mediation is engaged, the less entrenched the distortion is likely to be, and the more open parties may be to reassessment. An attorney who has spent three years and significant client resources building toward trial has invested—psychologically and professionally—in a particular outcome. The same attorney two months into litigation has not. Mediation’s off-ramp is widest before the case has been fully committed to an entrenched position.

Practical Takeaways

Create checkpoints. Build formal moments of reassessment at defined stages—after intake, discovery, and key depositions. Ask explicitly: Does the evidence gathered since the last checkpoint support my theory as strongly as I believe it does? Make a list of how opposing counsel will use the evidence and sit with that before you begin to refute it.

Be cautious about early advice. Distortion-driven confidence builds quickly once a leading preference emerges. Early client advice about the strength of a claim or defense may be the most contaminated by this effect, as it is given at a time when the least information exists to correct it.

Seek disconfirming information (and watch out for AI). The study points to earlier research that inducing a “counterargument mindset” lowers distortion and unwarranted confidence, although it did not eliminate it. Deliberately search for opposing views. Be thoughtful when using AI to build early case theories; its speed and polish can amplify bias by creating a false sense of completeness. Use prompts that specifically ask to critique or disprove your emerging theory.

Watch for the feeling of certainty itself. High confidence in a complex, contested matter may be a signal—not a conclusion. It is worth pausing to ask whether that confidence was earned by the evidence or generated by the process.

Conclusion

The Boyle and Nye study traces the mechanism by which confidence inflates during the decision-making process itself—through distortion of neutral information—in a way that speaks directly to the structure of legal practice. Lawyers are trained to develop a theory and do everything to advance it. That commitment has real value. But commitment and accuracy are not the same thing, and the same mental machinery that makes attorneys effective advocates may make them unreliable calibrators of their own certainty.

The mediation room, at its best, is one of the only places in litigation designed to interrupt the distortion process before confidence hardens into error.

NOTE

1. Peter J. Boyle and Pete Nye, “Information Distortion as a Source of Overconfidence in Managerial Decisions,” Judgment and Decision Making (2026, vol. 21:e3).

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