Harry Redknapp, the FA Cup-winning football manager, won a High Court battle yesterday, proving that police raided his home unlawfully as part of an investigation into alleged corruption.

Lord Justice Latham condemned the City of London Police for “wholly unacceptable” failures in obtaining and executing a warrant to raid Mr Redknapp’s home in November.

The decision heralds the end of a culture compared by his solicitor to that of a “police state” where forces use searches as a routine method to gather information.

The force was ordered to pay the Portsmouth FC manager and his wife, Sandra, £1,000 damages and 25 per cent of his legal costs, believed to be more than £10,000. The case has cost the taxpayer about £50,000.

The High Court decision is also a severe blow to the force’s investigation into corruption in football because addresses linked with five senior football individuals were named on the same warrant now judged to be flawed. Legal sources believe that police may have to return anything seized from the homes of the Rangers midfielder Amdy Faye, the Portsmouth chief executive Peter Storrie, the Leicester City chairman Milan Mandaric and the agent Willie McKay.

Papers and a computer had already been handed back to Mr Redknapp.

The City of London Police, the country’s top fraud-investigating force, was humiliated in December by the collapse of the £10 million trial of the champion jockey Kieren Fallon and others for alleged race fixing.

The judge, sitting with Mr Justice Underhill, complained of “slipshod” completion of warrants to raid properties. “The obtaining of a search warrant is never to be treated as a formality,” the judgment read. “It authorises the invasion of a person’s home.”

Mr Redknapp was seething about the raid on his home in Sandbanks, Dorset. His wife was at home while he was returning from watching a match in Germany. Photographers were there and pictures appeared in The Sun.

When Mr Redknapp went voluntarily to meet officers at Chichester police station later that day, he was arrested and put in a cell, a decision that did nothing to soothe his frustration. He was freed on bail.

Mr Redknapp sued City of London Police and has won on two grounds. His lawyers argued successfully that the police failed to explain why they needed a warrant: why they thought that they could not communicate with the occupier, why the occupier would not let them in or why it was suspected that the subject of the investigation might destroy evidence. The judges, however, added that the officers involved had not acted in “bad faith”.

The other successful argument by Mr Redknapp’s lawyers was that the document omitted his address. The raid was therefore deemed as trespass and police were ordered to pay damages, which will be donated to charity.

Mr Redknapp’s solicitor, Mark Spragg, a fraud and white-collar crime specialist, said that forces were too quick to resort to what he called draconian powers. “It is an outrageous abuse. His wife is still utterly in shock. The problem is that they are issuing these warrants all the time but it’s very rare that people take the police on and complain about it. Obviously more people should do. Otherwise they are behaving like a police state. There are many other ways they could get documents from people. They could ask.”

The investigation is into allegations of corruption surrounding player transfers. City of London Police said: “We accept the judges’ decision. We have already reviewed our procedures and will be working to ensure that warrants meet current guidelines.

“Having consulted with the Fraud Prosecution Service we are satisfied that nothing contained within the judgment has any impact on the main body of evidence.”

Mr Redknapp was reinterviewed by City of London Police last night, as part of a pre-existing arrangement.

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