New league tables for the Crown Prosecution Service risk only "racing certainties" being prosecuted to ensure impressive statistics, it has been claimed.

David Blundell, Chief Prosecutor of the West Midlands, voiced concern about the new system as the first year of results rating the 41 CPS regions were released.

West Midlands CPS was rated 'fair' overall but 'good' in most critical aspects, including pre-charge decisionmaking, victim and witness service and leadership.

The Overall Performance Assessment was carried out by the CPS Inspectorate and covered the 2004/05 financial year. It is the first year comparative 'league tables' have been produced.

"It was inevitable with league tables for schools and hospitals there would be league tables for CPS regions," said Mr Blundell. "This is the way Government says is one route of driving up performance and lets the public make the comparison and makes us strive for the best.

"There would be something wrong if we were getting conviction rates of 90 per cent. It would mean we were taking out cases from going before magistrates or a jury. There would be a real risk of prosecuting only racing certainties.

"I hope in the West Midlands we would have the integrity to avoid that, of deciding every case on its own merits and and not have one eye on possible league tables. There will always be cases which don't result in a conviction. We are prosecuting cases where we think a conviction is more likely than not.

"I'm just a little bit nervous around percentage success in league tables."

Areas where the West Midlands CPS fell down were on ensuring successful outcomes and on adequate disclosure.

The inspectorate found the West Midlands criminal justice agencies brought 66,985 offences to justice in 2004/05, almost 19,000 below the target for the year and unsuccessful outcomes in the magistrates' and crown courts was 22.9 per cent.

Mr Blundell said the region's rate of successful outcomes had steadily improved since the report was made, with pre-charging advice ensuring cases were solid before they went to court.

Figures for January 2006 show the number of successful convictions standing at 83.9 per cent against an 82.9 per cent national average, he said.

"In the critical aspects we were rated 'good' and I was encouraged by that. A fair rating is satisfactory but with scope for improvement.

"At the time the assessment took place we had been going through a period of tremendous change, introducing all the major criminal justice concepts, such as pre-charging advice.

"It is important to look at the category of cases too because some are more important to the public. The

report makes the point we've had tremendous success on higher profile cases. In December we had seven murder prosecutions and five were successful."

One factor which sits well with better victim support, better court time usage and fewer discontinuance episodes is West Midlands CPS's intention to cover up to 90 per cent of magistrate court cases in-house within three years. The proportion currently stands at 70 per cent. By the end of the year it hopes to have increased the number of higher court advocates, who can prosecute at crown court, from 17 to 30.

"We will be able to see cases through from start to finish," said Mr Blundell. "The Bar finds it quite difficult to do this at the moment because of the uncertainty of the length of court cases."