Academics Unplugged - Dr Amy Wilson

Cocaine on banknotes: how strong is the evidence?

Measurements of traces of cocaine on banknotes are used as forensic evidence of illicit drug activity. But all banknotes are contaminated with cocaine, so how should this evidence be interpreted in court?

In this presentation I will describe how Bayes theorem provides a logical framework for interpreting forensic evidence and how this framework can be applied to cocaine on banknotes.