Police chiefs have won a battle at the UK's highest court with a 90-year-old peaceful political campaigner who wants details about his attendance at various protests removed from an ''extremism'' database.

Supreme Court justices overturned an earlier ruling in favour of war veteran John Catt, from Brighton.

Mr Catt, who is of good character, argued that as he has not engaged in any criminality, the continuing retention of data about him on the National Domestic Extremism Database is unlawful and breaches his right to privacy under Article 8 of the European Convention on Human Rights.

In March 2013, he won his case at the Court of Appeal after a defeat at the High Court the previous year.

In December, the Metropolitan Police Commissioner and the Association of Chief Police Officers (Acpo) asked a panel of five Supreme Court judges to overturn the Court of Appeal ruling.

Today, the justices allowed the police appeal by a majority of four to one.

When the case was at the Court of Appeal judges ruled that the continuing inclusion of information on the database involved an interference with Mr Catt's right to respect for his private life, and that the interference could not be justified in his case.

They said information about Mr Catt was at first retained lawfully, but it continued to be held for a "disproportionate" length of time, violating Article 8.

Lawyers for the police submitted during the latest proceedings that the retention of information continued to be lawful.

Mr Catt first took legal action after Acpo refused his request to permanently delete all the data retained about him.

Personal information relating to Mr Catt is on a database maintained by the National Public Order Intelligence Unit, originally under the supervision of Acpo and now under the Metropolitan Police Commissioner.

The data at the centre of the case comprises records or reports made by officers overtly policing demonstrations of protest group Smash EDO.

It has carried on a long-running campaign calling for the closure of EDO, a US-owned arms company conducting lawful business. It has a factory in Brighton.

The Court of Appeal said some of the core supporters of Smash EDO were prone to violence and criminal behaviour, "but it is accepted that Mr Catt has not been convicted of criminal conduct of any kind in connection with any demonstrations that he has attended".

After the ruling, Mr Catt said in a statement: "Four senior judges have found that my rights have been violated unlawfully, whilst four others have disagreed.

"I cannot agree that the police in this country should be trusted with information about innocent people's lawful political activities.

"In my view, without a new system of rules governing police surveillance, there is too much scope for the police to abuse their powers.

"I am therefore left with no option but to take this matter to the European Court of Human Rights for the sake of other innocent people whose lawful political activities are being monitored by the state."

His solicitor Shamik Dutta of Bhatt Murphy said: "Mr Catt has instructed me to seek a ruling from the European Court that by monitoring and retaining information about people's lawful political activities, the UK is violating the privacy rights of its citizens."