An Appeal Court ruling has cast serious doubt over the extent to which police enjoy public interest immunity which shields them from civil damages claims for alleged negligence.

Case law includes a host of decisions in which members of the police have side-stepped action against them on public interest immunity grounds. But now the Court of Appeal has held that, while police may enjoy such immunity in a wide variety of cases, it must not be viewed as 'blanket immunity'.

The decision came as a result of interlocutory moves by the Northumbria Police Force to strike out a personal injury claim made against it.

The claim at the centre of the action involved a couple who gave police information about an incident in which a policeman died after being hit by a vehicle he was attempting to stop. The couple became victims of a campaign of threats and ultimately had to give up their business after police documents revealing their identity and the nature of the information they had given fell into the wrong hands. This occurred as a result of papers being stolen from a police vehicle.

The couple then launched a personal injury damages action against the police, accusing them of negligently failing to keep secure the information which they had been give in confidence.

However, the police won an order from District Judge Lancaster at Newcastle in July 1994 striking out the action on the grounds that it was not in the public interest that the police should face a negligence claim in such circumstances.

But that ruling was over-turned by Mr Justice Laws in the High Court last January, and now the Appeal Court has upheld the High Court ruling.

Lord Justice Hirst said in the Court of appeal that although police were generally immune from negligence actions over their activities, immunity was not 'blanket immunity'.

The decision is one which solicitor Bruce Howorth, of Newcastle firm Hay & Kilner, views as an important one.

"For a start, I don't think there is any other authority dealing with the situation where a person has provided information for the police and subsequently police have lost that information with the result that the person giving the information has suffered," he said.

"Of course, what has taken place so far has to be regarded in the context of winning a battle rather than the war. These were interlocutory proceedings and the final case still has to be heard. However, on the basis of the Court of Appeal ruling it has been made clear that police do not enjoy blanket immunity and that is important."

Howorth, who is predominantly a personal injury practitioner, but who has previously been involved in other action against the police, said he was not surprised by the police action to strike out the claim as such moves are frequently made when cases are launched against them. However, he said he was prepared for them to act as they did and was geared up to challenge it.