A SCIENTIST claims to have beaten a speeding charge after the device he developed proved he was doing 12mph less than the police had claimed.

Dr Phillip Tann appeared before magistrates after police said he was caught driving at 42mph.

But records from his invention showed he was travelling just under the 30mph limit.

The prosecution has been discontinued and the 45-year-old inventor claims the decision was made because data from his device proved the police camera wrong.

However, the Crown Prosecution Service said the case was dropped because the camera officer had left the force and could not attend the court hearing.

In November last year, Dr Tann was clocked by a mobile speed camera while driving through Sunderland.

He insists that his Autopoietic tracking system - which he had developed during the previous two years and he claims can measure data over distances of less than half-a-metre - calculated his speed at 29.177196mph.

When he received a letter and fine, he challenged it through the courts. After several pre-trial hearings, the Crown Prosecution Service told his solicitor that the case was being dropped.

The system, which can be installed on a mobile phone, records the location and speed of the handset on a computer database.

Dr Tann, whose business, Autopoietic Systems (Tann Ltd) is based in Birtley, said: "When I received the fine, I checked the database.

"The system I was testing is more accurate than anything else on the market and it said I was only doing 29.177196 mph at that time."

Dr Tann, from South Shields, pleaded not guilty at Sunderland Magistrates' Court.

He said: "The cameras used are not 100 per cent accurate, but my system is."

A spokesman for the Crown Prosecution Service said: "The reason for discontinuing the case was not because the Crown Prosecution Service accepted that Dr Tann's system was more accurate than the police speed camera.

"The reason the case was being discontinued was because the police officer operating the equipment had retired from Northumbria Police and was not willing to attend court.

"Without his evidence, it would not be possible to prove the case."

Northumbria Police said they were satisfied the camera reading was accurate.