Is bias alive and well in police investigation?

I wondered this when I overheard a police officer comment, “The truth is somewhere in between”. He was investigating an incident and getting statements from different parties about what happened. Based on his comment, there didn’t seem to be any room in his thinking for one party’s view to be correct about what happened. I can’t say if he came with that mind-set – that’s the way all police officer’s think – or just how he thinks.

His comment is an example of implicit bias as discussed in depth by three Toronto police officers at an expert witness conference. (Refs 1, 2) The officers described implicit bias and explained how to deal with it. The two days of lectures on bias were excellent.

(I attended this conference and gave an invited talk on the principles governing cost control in dispute resolution. (Ref. 3)

Implicit can be defined as capable of being understood from something else though unexpressed. (Ref. 4) The problem is the something else is not explained. Is it reliable or no?

If the something else is the result of an analysis of the evidence leading to a conclusion like the “truth is in the middle”, that’s fine. But, generally, police officers on-the-run are not analysing evidence, they’re focusing on collecting it for analysis later by others.

And analysis itself is an exacting process. Think the scientific method. Also the two year course on data analysis offered by a college in Ontario – that’s two years learning the principles of data and evidence analysis. (Ref. 5)

I met a Nigerian chap who is in Canada enrolled in the two year course. He’s learning how to analyse data, facts and evidence to see where they lead. I mentioned the scientific method and he was quick to acknowledge that was part of it. I don’t think the police train like this, as a rule, to analyse evidence and statements by parties to an incident to see where the truth lies.

I’m certain police officers are trained in the collection of evidence, and analyzing it on-the-go in some situations. Witness what went on in Saskatchewan as I was writing this – police officers were analyzing evidence on-the-fly trying to find a mass murderer. But analyzing evidence as they collect it is not the rule.

You collect and analyse evidence by being thorough and objective, and on guard against implicit bias – a cardinal rule in forensic engineering investigation as carried out by experts.

We deal with implicit bias according to the Toronto police by: (Ref. 1)

  1. Understanding implicit bias
  2. Identifying the bias
  3. Reducing it
  4. Mitigating for the bias of your audience


I think implicit bias is alive and well but well suppressed by investigating police officers. It just manages to poke it’s head up from time to time. Bias saw the light of day for a moment in the comment by the chap I chanced to overhear but it’s not the rule. I know this to be true – police objectivity – from my 19 years volunteering with a police victim services unit and working with police officers.


  1. Virji, Aly, Staff Sergeant and Moosi, S. Ali, Constable, Toronto Police Service, Addressing Implicit Bias On and Off the Stand, 3rd Annual Expert Witness Forum East, Toronto, February 27, 2018
  2. Duncan, Peter, Instructor, Toronto Police Service, Addressing Implicit Bias: Interactive Session, 3rd Annual Expert Witness Forum East, Toronto, February 27, 2018
  3. Principles governing the cost control of dispute resolution and claim settlement involving experts. Posted July 30, 2019. Updated September 24, 2020 and March 18, 2021
  4. Merriam-Webster and Oxford Dictionaries
  5. Data Analytics for Business, St. Clair College, Windsor, Ontario


  1. Expert witness forum looks at bias and other touchy subjects in forensic work. Posted March 8, 2018
  2. Are experts being broadsided by bias, unbeknownst to them? Posted April 12, 2018

(Posted by Eric E. Jorden, M.Sc., P.Eng. Consulting Professional Engineer, Forensic Engineer, Geotechnology Ltd., Halifax, Nova Scotia, Canada. September 20, 2022   

Comments are closed.