Not only can Pat use pollen to tell who has been where – by mapping their clothing she can even tell which part of a suspect’s body did what.

Pat recalls a case of attempted murder in Hertfordshire, where a man had tried to strangle a woman underneath a lamppost:

Whereas DNA and fingerprints are the evidence that a criminal leaves behind, pollen is the evidence that gets left on the suspect.

“He said he hadn’t been there of course, but by taking his clothing apart I showed that he’d bumped up against a fence with his left shoulder, that he’d dragged her through a hedge, that he’d knelt, and so on.”

Because she had sampled the crime scene in detail, she was able to see where precise bits of his body had been and accurately reconstruct exactly what he did at the time.