At the height of the Troubles, Philip Campbell Smith operated at the cutting edge of the British Army's fight against terrorism, helping to run informants for an elite and top secret military unit that operated on the murderous streets of Northern Ireland.
After leaving the forces, the 53-year-old continued to operate in the shadows, this time as a private investigator with his own thriving business and a burgeoning client list that included law firms, insurance companies and currency dealers.
But the extent to which Campbell Smith's clandestine past as a servant of the state became warped into a criminal search for profit was laid bare in a west London courtroom yesterday as a prosecutor outlined how he repeatedly used a specialist "blagger" on behalf of customers to illegally obtain private and confidential information including details of bank accounts and phone calls, as well boasting that he could obtain medical records and Interpol files.
The ex-soldier was appearing with the three others, including his business partner, at a sentencing hearing for committing fraud by conspiring to access private information. The proceedings are not the only legal issue facing Campbell Smith, who is also at the centre of allegations of computer hacking on behalf of the News of the World. The private investigator is of interest to Operation Kalmyk, a Scotland Yard inquiry into allegations that several dozen individuals were targeted for email hacking carried out for the defunct tabloid.
But in a case which offers evidence of how the practice of gathering illegal information went beyond newspapers and into the commercial world, a judge at Kingston Crown Court heard how Campbell Smith and his co-defendants targeted a series of public and private bodies, including bank, the DVLA, the Criminal Records Bureau, police databases, Interpol and HM Revenue and Customs.
Under the auspices of Northamptonshire-based Brookmans International, the company he founded in 2006 with business partner Graham Freeman, Campbell Smith told clients that he could obtain information which, if his methods became known to the authorities, could lead to him being sent to prison.
When he was eventually arrested in 2009 by officers from the Serious and Organised Crime Agency (SOCA), Campbell Smith told detectives that he had accessed "stuff, dodgy stuff" that he accepted breached data protection laws.
The court heard that the former intellligence officer used Daniel Summers, 32, an alcoholic who specialised in "blagging" private data by calling banks, phone companies and other organisations and impersonating targets or pretending to be an employee to obtain confidential details. Prosecutors described Summers, from Teddington, west London, as the "lynch pin" who "hoodwinked, lied and cheated" into the supposedly secure databases of large corporations and public agencies.
Sandip Patel, prosecuting, told the court that Summers, whose lawyer told the court he was acting more as a "footsoldier" for the private investigators, charged a range of fees for his services, from £75 for details of a single bank transaction to £200 for a bank statement. In turn, Campbell Smith and Freeman charged their clients, who were not named in court, higher rates and in one case invoiced a customer £14,000.
When he was arrested, Campbell Smith told police: "What I have done is wrong. I have been stupid and naive. I have been caught out this time. I don't know what happens [with the information] further down the line."
Due to the legal proceedings it was not until this week that the former soldier's alleged involvement in computer hacking could be made public.
He is claimed to have targeted Ian Hurst, a former colleague in the British Army's Force Research Unit (FRU), an ultra-sensitive covert group which was in charge of running Republican and Loyalist terrorist informers and was later implicated in a number of assassinations and murders in Northern Ireland. A BBC Panorama investigation last year broadcast allegations that Mr Hurst's computer was planted in 2006 with a so-called Trojan virus that replicated emails as part of a commission from the NOTW and one of its senior editors, Alex Marunchak. Among the downloaded material were messages relating to a top-level IRA agent, Freddie Scappaticci or Stakeknife, who was run by Mr Hurst and regarded as being at high risk of assassination.
Mr Hurst is currently suing Campbell Smith, Rupert Murdoch's News International and private investigator Jonathan Rees, whose Southern Investigations company was also employed by the NOTW, for damages relating to the alleged email hacking.
The court heard that Campbell Smith, with a previous conviction for soliciting a prostitute, had also pleaded guilty this week to possession of three rounds of specialist ammunition he had retained since his military service.
He and his co-defendants are due to be sentenced on Monday at the end of a two-day hearing. Adam Spears, 72, a former Metropolitan Police detective who also employed Summers, will also be sentenced after admitting fraud.