The director of public prosecutions, Sir David Calvert-Smith, yesterday announced a crackdown on lethal drivers after a report by the crown prosecution service inspectorate found that too many motorists who caused deaths on the roads were escaping serious charges.

The independent CPS inspectorate found that in six of a sample of 99 cases, drivers who should have gone for jury trial on charges of causing death by dangerous driving were instead prosecuted for the lesser offence of careless driving.

The report said juries in recent years had become more willing to convict on dangerous driving charges, but not all prosecutors were aware of that development.

Sir David said he would be issuing guidance to prosecutors in the light of the report. "I am concerned that not all prosecutors have taken on board the readiness of juries these days to convict in cases of causing death by dangerous driving. We need to be consistent in our approach to these cases which can devastate families who lose their loved ones as a result of a car crash."

On the whole, the report found, road traffic fatalities were better handled than other cases, but it recommended that cases should be dealt with by prosecutors with specialist training to ensure consistency, better case management and better liaison with police.

Sir David said the CPS would now look at appointing a specialist in these cases for each of the 42 CPS areas. "A specialist prosecutor could help provide a second opinion to colleagues, when appropriate, in cases where a road traffic accident results in a fatality," he said.

"Setting up such a team of expert prosecutors who are familiar with the most up-to-date developments in this area of law would help in ensuring decisions are consistent throughout England and Wales."

He said the CPS would continue to refer those cases where the sentence was thought to be unduly lenient to the attorney general for him to take the case to the court of appeal, particularly fatal drink-driving cases.

The number of people who died on British roads last year was 3,450 compared with 3,409 in 2000.

An estimated 20% of accidents are caused by falling asleep at the wheel and it is believed these account for around 300 deaths a year. Driving between midnight and 6am carries the highest risk for drivers, and the Department of Transport has also warned against taking long trips between 2pm and 4pm.