​Forget fingers, eyes or even ears.

Scientists at the University of Bath believe they may be able to sniff out criminals by looking at the shape of their nose.

As people grow more concerned about illegal immigration and identity theft, experts are looking for a person’s physical characteristics, known as biometrics, to confirm they are who they say they are.

Unlike other facial features, such as eyes or ears, noses are difficult to conceal and are not changed very much by a person’s expression.

Dr Adrian Evans and Adrian Moorhouse, from the university’s electronic and electrical engineering department, have been using a photographic system called PhotoFace to scan the 3D shape of volunteers’ noses.

Their results showed that nose scanning had a good potential for identifying people.

Dr Evans said: “Noses are prominent facial features, and yet their use as a biometric has been largely unexplored.

“We wanted to find out how good they could be at recognising individuals from a database.

“There’s no one magic biometric - irises are a powerful biometric, but can be difficult to capture accurately and can easily be obscured by eyelids or glasses.

“Noses, however, are much easier to photograph and are harder to conceal, so a system that recognises noses would work better with an uncooperative subject or for covert surveillance.

“We’ve only tried this on a small sample of people, but the technique certainly shows potential, perhaps to be used in combination with other identification techniques.”

The researchers discovered that there were six main nose shapes; Roman, Greek, Nubian, Hawk, Snub and Turn-up.

Their computer software used three characteristics from the nose; the ridge profile, the nose tip and the nasion - the section between the eyes - and a combined ratio could then be used to distinguish between people.

Professor Melvyn Smith, who led the team at the University of the West of England which developed the PhotoFace system, said he was excited by the research.

He said: “This collaborative project with Bath is very exciting work with great potential.

“PhotoFace works by taking photos lit by a flash from several different angles so that four images are taken in very rapid succession of every point on the face, each under different controlled lighting conditions.

“The software then works out the colour, surface orientation and depth of each point on the face by analysing the shading within each of the photos.”

The researchers are now hoping to build up a larger databases of noses to test to see if it can pick out individuals from a larger group of people and also distinguish between members of the same family.