Much is now understood about cognitive bias and the implications for decision-making. Unfortunately, that understanding is rarely applied in the criminal justice process. The Health and Safety Executive (‘HSE’) is more advanced than some investigating authorities in that it recognises and even provides some limited guidance on the issue. Their guidance ‘Investigating accidents and incidents’ (aimed principally at organisations but also reflective of HSE practices) provides: “The investigation should be thorough and structured to avoid bias and leaping to conclusions. Don’t assume you know the answer and start finding solutions before you complete the investigation. A good investigation involves a systematic and structured approach.”