In reality, people who conduct investigations are susceptible to both conscious and unconscious bias.
An investigator may be biased based on outside influences, such as the media's portrayal of harassment at work or past experiences with employees.
Everyone can think in a way that involves unconscious bias at some point, but it's important to be aware of it and not let it affect behaviour or decisions.
Confirmation bias is another to avoid all together. This is where we look for patterns to confirm our point of view. It's important to focus on the present.