PRIVATE investigator Glenn Mulcaire has lost a Supreme Court fight to keep the identity of the person who instructed him to intercept messages a secret.
Mr Mulcaire, who intercepted mobile phone messages while working for the News of the World, failed to persuade the UK's highest court that he should be able to rely on privilege against self-incrimination in civil phone-hacking proceedings.
He had asked five Supreme Court justices to rule on whether he must disclose who instructed him.
Mr Mulcaire said his lawyers advised him that he should not have to give "potentially incriminating answers" to questions asked in civil litigation at the High Court, and the appeal was made to protect his "legitimate legal interests".
Five years ago Mr Mulcaire and former News of the World royal editor Clive Goodman were jailed after the Old Bailey heard that they plotted to hack into royal aides' telephone messages.
At the Supreme Court today, the five justices unanimously dismissed his appeal.
Mr Mulcaire says he is at risk of being charged with criminal offences, and faces damages claims at the High Court, many of which have been brought by celebrities.
He fears he may incriminate himself if he answers questions in the civil proceedings.
Mr Mulcaire appealed to the Supreme Court after losing fights in the High Court and Court of Appeal.
His battle began after Nicola Phillips, who was an assistant to public relations consultant Max Clifford, claimed her voicemail had been unlawfully intercepted.
Judges in the High Court and Appeal Court ruled that Mr Mulcaire should disclose information relating to Ms Phillips's claim.
Mr Mulcaire was again arrested in December following the launch of a new police investigation, the Supreme Court was told at a hearing in London in May.
A lawyer told the judges Mr Mulcaire had been released on bail without charge pending further inquiries.
Mr Mulcaire said in a statement released before the start of the Supreme Court hearing: "The police have all the relevant documents from me since 2006 and I have already faced criminal proceedings, been convicted, and served a prison sentence.
"All the steps taken by my legal team in respect of the civil claims against me are to protect my legitimate legal interests."
Today's ruling was made by Lord Hope, Lord Walker, Lord Kerr, Lord Clarke and Lord Dyson.
Lord Walker, announcing the decision of the court, said the appeal "arises out of what has become known as the phone-hacking scandal".