Confirmation bias

How does confirmation bias come into play in accident investigations?

Ryan Gledhill, solicitor from OAH, explains how cognitive biases can affect how we investigate accidents.

What do we mean by confirmation bias?

The most prevalent cognitive bias in an accident investigation is confirmation bias.

In the aftermath of an incident, a robust investigation is a key tool in identifying the causes, wider regulatory context, and learning points to take forward.

A flawed investigation can produce remedial actions that do not address the true underlying causes. This could mean investing time and money into the incorrect areas.

One cause of such an investigation that we often overlook is the investigator’s mindset.

The HSE’s Guidance on Investigating Accidents and Incidents raises the issue of bias, stating any investigation “should be thorough and structured to avoid bias and leaping to conclusions”.

Where does confirmation bias come from?

Investigators are only human and share the same unconscious and cognitive biases we all hold. These stem from natural psychological processes that evolve to allow us to cope with complexity.

These mental shortcuts, known as heuristics, are helpful and allow us to filter masses of information and save time.

For example, when you need a specific item in the supermarket, you go to the aisle where you last saw it.

So, what cognitive biases can affect an investigation?

The most prevalent one in an accident investigation is confirmation bias.

This is the tendency to search for, focus on, or remember information that confirms one’s preconceptions.

Of course, our brains will always naturally look for a starting point for an opinion. In fact, early iterations of our primitive species would have been rewarded for quick decision making. So, we have evolved to do the same.

Confirmation bias presents itself as a silent voice telling you to carefully look at specific evidence that supports your initial hypothesis. As a result, you look less closely at other evidence.

So how can you block out this voice and ensure that you are carrying out a truly open investigation?

How to avoid confirmation bias in accident investigation

One way is to actively seek evidence that contradicts what you believe to be the conclusion.

Another is to discuss evidence and findings with another person, getting them to play devil’s advocate.

As an investigator, a sound knowledge of biases and heuristics is vital.

After all, it’s your job to make decisions and this is essentially the science of how decisions are made.

The HSE advice in their ‘Investigating Accidents and Incidents’ document is that to be free from bias, the analysis must be carried out “so all the possible causes and consequences of the adverse event are fully considered.”

Something as simple as reminding yourself confirmation bias exists as you begin your investigation may be enough to focus your mind and broaden your scope of the investigation.

What’s an example of confirmation bias?

A recent OAH case provides a good example of confirmation bias.

The firm received an instruction to carry out an internal investigation into an apparent suicide attempt.

This theory was part of the initial speculation that the person was in a location they shouldn’t be in.

OAH carried out its own inspection of the location. With an open mind, the firm identified, preserved and analysed all of the evidence which overwhelmingly showed it was not a suicide attempt at all.

In another case, OAH received an internal investigation report with a conclusion as to what had happened without any supporting evidence.

When the firm probed, it became clear the investigator had simply determined what they thought had probably happened based on their experience.

In fact, when we reinvestigated it, the facts and conclusions were completely different, and the learning was different.

Final thoughts on cognitive bias at work

The most important thing to remember? These mental processes and biases are mostly unconscious.

Of course, as investigators, you don’t intend to be closed-minded, jump to conclusions, or ignore information that contradicts your existing ideas.

It’s our natural way of dealing with everyday life to take shortcuts in processing large amounts of information we encounter each day.

So, what if simple awareness of bias isn’t enough to prevent it? The best way to overcome our habits may be to work as a team and bring in fresh ears and eyes to challenge your ideas.

Ryan Gledhill – Solicitor – Osborn Abas Hunt.