Some basic trigonometry can deliver vital evidence from the scene of a crime.

A bit of graph theory can help to identify key players in a criminal network.

Inverse problems are mathematical detective problems. They can help solve crimes, are used in medical imaging, and much more.

Using maths to simulate the behaviour of criminals.

How the maths that is used to predict earthquakes can help fight gang crime.

Networks loomed large at the AAAS annual meeting in Vancouver, in particular the one you're looking at right now: the Internet. Plus went along to a session on web surveillance. It sounds sinister at first, but as we found out, it's not all about Big Brother breaching your privacy. Information on the web can help us catch terrorists and criminals and it can also identify a widespread practice called astroturfing.

Maths is not the first thing that springs to mind when you think about fighting crime. But a closer look reveals that it is behind many of the techniques that modern detectives rely on. Chris Budd investigates.