Page 154 - Magistrates Conference 2019

 Omissions
 Demeanour [Of limited value – material error for the entire decision to turn on

demeanour assessment] – See Horace Reid v Dowling Charles and Percival Bain
Privy Council Appeal No. 36 of 1987, Mumtaz Properties v Ahmed [2011]

EWCA 610

 Previous convictions and how they may be relevant to credibility
 Other factors

Bias in judgment

A Magistrate should not let any bias or unconscious bias affect his reasoning. Bias is any
inclination or prejudice for or against one party. Unconscious bias is hidden bias or

subconscious bias or automatic bias. It is understood that individuals have preferences at a
subconscious level that influence decision making. This is part of a natural process of

categorising similar objects together. The related cognitive biases can result in an individual’s

implicit reliance on stereotypes. This implicit reliance on stereotypes can influence how
incoming information is interpreted and remembered.

Categories of bias

• Affinity bias or mini me syndrome - making choices based on affinity/similarity;

• Conformational behaviour - we make decisions largely in a way that is designed to
confirm beliefs we already have;

• Assimilation bias - an inclination to interpret ambiguous information in a way that is
consistent with previously held beliefs;

• Belief perseverance - keeping held beliefs after evidence on which they were founded

have been shown to be invalid or false. This could be a result of a tendency to ignore
or filter out evidence that disconfirm our beliefs. This is a particular pertinent issue

with regard to judging. How much do we select evidence that suits our view and leave

out possibly relevant material which does not support our view?
• Argument from authority - believing that an idea posited by a likeable source is true

and that an argument put forward by an unlikeable source is not;

• Argument from novelty - believing because something is new it must be better;
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