A TEAM of North-East scientists have made a breakthrough which is expected to revolutionise forensic science.

Researchers at Teesside University have developed a way of detecting minute blood stains which would not be seen using current technology.

They have also found a way of checking the age of blood stains - something which is regarded as a holy grail of forensic science.

The failure to locate traces of blood during the original forensic examinations meant that the killers of both Stephen Lawrence and Damilola Taylor evaded justice.

It was only years later that traces of blood were identified and the killers were eventually brought to justice.

Experts hope the new blood detection technique will help investigators avoid these mistakes in the future.

It works by using a technique known as visible wavelength hyperspectral imaging.

This allows for the positive identification of blood which may be confused with other red coloured substances.

It also enables investigators to pinpoint the age of a one month old blood stain to within one day.

Chemist Dr Meez Islam, who is one of the academics behind the forensic breakthrough, which also involved his colleagues Liam O'Hare, Peter Beveridge and PhD student Bo Li, said: "Often you go to crime scenes and what appears to be blood isn't blood.

"Blood on dark backgrounds can be hard to see and there are traces of blood that are not visible to the naked eye.

"We have developed a technique which is a non-contact, non-destructive way of detecting and identifying blood.

"We use a camera with a liquid crystal tuneable filter which takes a series of pictures at different wavelength bands and can identify blood stains through its unique absorption spectrum.

"It can quickly differentiate between what is blood and what isn't and it can locate blood stains on problematic areas such as red clothing or dark backgrounds and at diluted amounts.

"What this does is provide fast, at the scene identification of blood and speeds up the investigative process as items do not need to go back to a laboratory to be examined."

Dr Islam and his team currently have a prototype instrument and are in talks with manufacturers about developing a commercial instrument.

"Current methods for age determination of blood stains are neither accurate, reliable, robust nor useable at a crime scene," said Dr Islam, who said the development was potentially "a huge step forward" for forensic science.

To mark the 21st anniversary of forensics at Teesside - which was the first university to offer crime scene courses - a special celebratory event is taking place at the university on Thursday, November 7.

Bestselling crime writer Val McDermid, famous for her Wire in the Blood series, will be the guest of honour and will talk about how scientific fact is now informing fiction.