An 89-year-old political campaigner's fight to have details about his attendance at various protests removed from a police ''extremism'' database is to reach the UK's highest court.

In March last year the Court of Appeal ruled in favour of John Catt, from Brighton.

But police will challenge that decision at a hearing at the Supreme Court.

Mr Catt, who is of good character, argues that, as he has not engaged in any criminality, the retention of data about him on the National Domestic Extremism Database is unlawful.

He originally lost his case at the High Court in 2012 when he failed to persuade two judges to order the removal of details about his activities from the database, which is operated by police chiefs.

At that stage Lord Justice Gross and Mr Justice Irwin dismissed his judicial review claim, ruling that his right to privacy under Article 8 of the European Convention on Human Rights was not infringed.

Last year three appeal judges in London said the inclusion of personal information relating to Mr Catt on the database ''does involve an interference with his right to respect for his private life which requires justification''.

Master of the Rolls Lord Dyson, Lord Justice Moore-Bick and Lord Justice McCombe said they had reached the conclusion that the ''interference with Mr Catt's right to respect for his private life has not been justified and that the appeal must therefore be allowed''.

Mr Catt said in a statement at the time that he hoped the decision of the appeal judges "will bring an end to the abusive and intimidatory monitoring of peaceful protesters by police forces nationwide".

His legal action followed the refusal of the Association of Chief Police Officers (Acpo) 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.

Judges have been told that his fight was for ''a citizen's right lawfully to manifest his political views without being labelled a domestic extremist subject to a special and apparently arbitrary form of state surveillance''.

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 that 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''.

Announcing the decision in favour of Mr Catt, Lord Justice Moore-Bick said the ''overriding principle is the need to strike a fair balance between the personal interest of the claimant in maintaining respect for his private life and the pursuit of a legitimate aim in the interests of the public at large''.

He said: ''We do not doubt the importance to modern policing of detailed intelligence gathering and we accept the need for caution before overriding the judgment of the police themselves about what information is likely to assist them in their task.''

He said: ''The systematic collection, processing and retention on a searchable database of personal information, even of a relatively routine kind, involves a significant interference with the right to respect for private life.''

It could be justified by showing that it serves the public interest in a ''sufficiently important way'', but in Mr Catt's case it had not been shown ''that the value of the information is sufficient to justify its continued retention''.

The Court of Appeal ruling is being challenged by the Metropolitan Police Commissioner and Acpo during a three-day hearing before Supreme Court president Lord Neuberger, sitting in London with Lady Hale, Lord Mance, Lord Sumption and Lord Toulson.

They will also hear submissions on behalf of Mr Catt, who is expected to attend.

War veteran Mr Catt said in a statement: "This hearing comes over five years since I first asked Acpo to explain the surveillance of my lawful political activities.

"In my view at every stage the police have failed to provide an adequate answer to my simple and straight forward question: how can they seek to justify in law the way in which they have sought to keep tabs on me and my lawful political activities?

"I look to the Supreme Court now to help them understand that this is simply not tolerable in a democracy of the kind for which I fought in the last war."

His solicitor, Shamik Dutta, of law firm Bhatt Murphy, said: "Mr Catt will rely upon the Human Rights Act to argue that there are insufficient legal safeguards to protect the privacy of innocent people who attend political demonstrations in this country."

He added: "If Mr Catt succeeds, the Home Secretary and police forces nationally will need to review the way in which they gather and retain information about citizens' lawful political activities."