Andrew Hayton, 30, of Weedon, Northamptonshire, who was freed last December after serving the original sentence, will now be returned to prison.
Three appeal judges, headed by the Lord Chief Justice, Lord Taylor, also doubled Hayton's four-year driving ban. They agreed with the Attorney General that the jail sentence was 'unduly lenient' in view of Hayton's three previous convictions for drink-driving.
Hayton had pleaded guilty at Peterborough Crown Court to causing the death of Sergeant Simon Lilley by reckless driving. The policeman died on 5 November 1991, while diverting traffic into a lay-by census point on the A5 at Weedon.
The court was told that Hayton, who had drunk five pints of lager, ran his machine into the officer at 60mph.