BIAS

Confirmation Bias —

Why Human Beings Begin Filtering Evidence Once They Believe They Are Right

One of the most difficult things for any human being is to publicly admit:“I was wrong.”

Our sense of self is closely connected to the belief that our judgments, decisions, and understanding of the world are generally sound. To discover that we may have misunderstood a situation, trusted the wrong conclusion, or followed the wrong path can feel deeply uncomfortable.

For many people, admitting error feels more than embarrassment.

It can feel like weakness, loss of credibility, or even fear that others may no longer trust our judgment.

As a result, the human mind naturally begins protecting itself.

Once we become emotionally invested in a belief, we often begin noticing information that supports our position while unconsciously overlooking information that challenges it.

Psychologists call this confirmation bias.

In everyday life this may simply lead to arguments, misunderstandings, or damaged relationships.

But within criminal investigations, courts, governments, media, and institutions, the consequences of confirmation bias can be life-changing — or, fifty years ago, fatal.

Importantly, bias does not always emerge from malice or deliberate dishonesty. Often it grows quietly through fear, pressure, loyalty, emotion, and the natural human desire to protect one’s sense of security and self-worth.

In my own case, a young police motorcycle officer had suffered a serious accident in the line of duty and was no longer physically capable of continuing in the only work he had known. Rather than dismiss him from the force and leave his young family without security, his superiors created another role for him within the police service.

After months of study, he qualified as a vehicle examiner and developed an excellent reputation for his work.

Years later, he was asked to examine my vehicle.

After approximately two hours, he reportedly informed detectives that the vehicle had not struck a pedestrian.

According to later evidence, the response he received was effectively:“Trevor, if you want a job here on Monday morning, you had better say it has.”

Faced with the fear of losing both his livelihood and the security of his family, he prepared a report which avoided explicitly stating that the vehicle had not struck anyone — but neither did it directly state that it had.

Over time, he appears to have gradually relied more heavily upon the conclusions already formed by investigators and less upon the contradictory evidence he himself had originally observed.

This is one of the most dangerous aspects of confirmation bias.

Human beings naturally seek consistency between what they believe, what others expect of them, and what they need emotionally in order to continue functioning.

Once that process begins, contradictory evidence can slowly become easier to minimise, reinterpret, or overlook entirely.

Public Commitment and Personal Identity

Another area of concern is something most human beings are guilty of at some point in life: forming conclusions based on what appears, at the time, to be the best available information.

In many ways this is both normal and necessary. Human beings constantly make judgments in order to function, protect themselves, and understand the world around them.

The danger begins when those conclusions become publicly defended positions rather than open questions.

Once we strongly commit ourselves to a belief — especially in front of family, friends, colleagues, or society — changing our mind can become emotionally difficult. Pride, reputation, fear of embarrassment, and personal identity can all become attached to the original conclusion.

If our belief later proves correct, there is no conflict.

But when reliable new evidence challenges what we once strongly defended, we are faced with a painful psychological choice:• acknowledge we may have been mistakenor• continue defending the original belief while minimising the new information.

Many people struggle with the first option, not because they are malicious, but because admitting error can feel like losing part of themselves.

I experienced this personally after my release from prison.

The original conviction had shaped how many people understood both me and the events surrounding the case. For years, those beliefs had been repeated, defended, and emotionally absorbed into personal histories and conversations.

When my exoneration eventually occurred, I could see genuine emotional conflict in some people who had long believed I was guilty. Accepting the new reality required them not only to reconsider the case, but also to reconsider years of certainty.

Perhaps the most tragic example involved the mother of my late girlfriend, the woman whose death I had been convicted of causing.

For many years she had understandably believed I was responsible. Even after the evidence changed, the emotional pain remained overwhelming. Her response reflected not hatred, but the enormous difficulty human beings sometimes face when grief, memory, and identity collide with a new and deeply confronting truth.

Confirmation bias is not always driven by dishonesty.

Sometimes confirmation bias is driven simply by the human need to emotionally survive what the truth asks us to accept.

However, the issue becomes far more serious when institutional pressures, career advancement, financial interests, or organisational loyalty begin reinforcing that bias.

At that point, the danger is no longer limited to ordinary human error.

The danger becomes systemic.

A justice system cannot rely solely upon the goodwill or personal integrity of individuals, because all human beings are vulnerable to emotional pressure, fear, pride, ambition, and self-preservation.

That is why strong safeguards matter.

Independent review bodies, full disclosure of evidence, transparent forensic procedures, and genuine accountability mechanisms are not designed to weaken police or investigators. They exist to protect the integrity of the justice system itself.

The goal is not punishment for honest human mistakes.

The goal is to ensure that no individual, institution, or authority becomes capable of controlling a narrative by concealing evidence that may challenge it.

Only when all relevant evidence is openly available can justice remain stronger than bias.

Perhaps the greatest danger is not that human beings make mistakes.

It is that once those mistakes become emotionally, professionally, or institutionally protected, truth itself can slowly become the enemy.

Next Edition:

“Institutional Momentum — Why Systems Resist Admitting Error”

Question for Readers:

How difficult do you find it to say:

"I'm sorry. I got it wrong. Please let me try to put it right."