Read all about it: The secret dossier of lawbreaking that spells trouble for Rupert Murdoch...and David Cameron

Rebekah Brooks was among journalists who used a private detective who was later convicted

(AFP/ GETTY IMAGES)

The News of the World paid a private detective to provide hundreds of pieces of confidential information, often using illegal means, a confidential document obtained by The Independent on Sunday has revealed.

The "Blue Book", a ledger of work carried out by Steve Whittamore for News International titles, including the NoW and The Sunday Times, details a series of transactions including obtaining ex-directory phone numbers, telephone accounts, criminal records checks and withheld mobile numbers. It reveals the itemised details of checks on public figures, including Peter Mandelson, ordered and paid for – at up to £750 a time – by reporters working for the redtop. Staff from a number of other national newspapers made similar requests, and their details are contained in further dossiers held by the Information Commissioner, the privacy watchdog.

Among the journalists requesting information from Mr Whittamore, who was later convicted of offences committed under the Data Protection Act, was the former NoW editor Rebekah Wade, now Rebekah Brooks.

The contents of the dossier were collated by the Information Commissioner following a raid on Mr Whittamore's Hampshire office in 2003, but the watchdog has previously refused to disclose its contents, to protect the identities of the people named within it.

The disclosure of the extent to which the NoW and its sister titles used the services of private investigators to obtain personal information by questionable means will add to the controversy threatening to engulf News International (NI), whose bosses have consistently denied any wrongdoing over the affair.

The wide-ranging extent of the phone hacking and other activities could damage NI's share price in the long run – and reduce the fortune of its boss, Rupert Murdoch.

One senior MP last night complained that the list revealed "a widespread and casual law-breaking" among people associated with NI.

But the existence of the Blue Book also threatens further embarrassment for David Cameron, the Prime Minister, who has so far supported Mr Coulson, now his chief spin-doctor. Mr Coulson resigned from the NoW in 2007 after one of his reporters, Clive Goodman, was jailed for tapping into telephone voicemails. Mr Coulson has consistently denied any knowledge of the illegal methods during his term as editor. He was appointed to the top post in January 2003.

However, the issue reignited last week when MPs voted to refer the issue to the powerful Standards and Privileges Committee following fresh allegations about what Mr Coulson really knew. The IoS revealed last week that the mobile-phone details of the former Labour minister Lord Mandelson were among lists of private data seized by police investigating phone hacking by NoW reporters during Mr Coulson's time as editor.

Now, the IoS can reveal that the Blue Book details a list of 1,027 transactions between Mr Whittamore and a client referred to as "Times Sun News of the World". The itemised spreadsheet lists highly confidential details, including the name of the journalist making the order, the service requested and the "target" of their investigation. Subjects include the former boxer Chris Eubank, former Labour minister David Lammy, and a target described simply as "Rooney".

Many of the tasks were carried out for reporters working for other titles in the group, and some would have been for legitimate journalistic investigations. Just 5 per cent – covering credit checks and searches on company directors – were definitely legal, almost 25 per cent were definitely illegal, with the remainder relating mostly to obtaining private addresses, which is a grey area.

Activity that definitely broke the law included tracing people using just a telephone number or vehicle registration, accessing ex-directory telephone numbers, obtaining details of hotel stays and running criminal records checks. Around half of the tasks covered finding out the full addresses of targets, which is illegal if the people involved have chosen to remove themselves from the public register.

The raid on Mr Whittamore's office during "Operation Motorman" in 2003 unearthed records of requests made by journalists for 13,343 different pieces of information. The Information Commissioner subsequently revealed that 305 journalists had been identified as Mr Whittamore's customers, "driving the illegal trade in confidential personal information".

The details were recovered from Mr Whittamore's house in March 2003, less than two months after Mr Coulson had been promoted to editor of the NoW. He had been appointed deputy editor in the summer of 2000.

During his time at the paper, in October 2000, the Regulation of Investigatory Powers Act modernised telecommunications law, effectively making a number of journalistic methods, including accessing someone's voicemail without permission, illegal.

A former Labour minister, Tom Watson, condemned the decision to keep the contents of the Blue Book secret for so long, and urged fellow MPs to investigate the new developments.

"This list has been kept under wraps and people will be appalled by that," he said. "The discovery of this list, all those years ago, was supposed to end this type of covert surveillance, but nothing happened."

'Blue book' Jargon buster

Breaking the code: Investigators at work

The 'Blue Book' details more than 1,000 transactions between the private investigator Steve Whittamore and News International publications. Each entry details the person making the request, the paper they work for, and the service requested. Here we explain some of the abbreviations and terms of reference and assess their legality:

CCJ Running a credit check, or seeing if a person has a county court judgment against them.

Illegal? No, used by credit firms.

Company Search Finding details of firms and their directors. Illegal? No.

Conv Finding out to whom a telephone number is registered. Illegal? Yes.

CRO Criminal records check. Illegal? Yes.

Dir Running a search on company directors. Illegal? No.

Endorsements Checking points on a driving licence. Illegal? Yes.

F+F Identifying names of Friends and Family phone numbers. Illegal? Yes: requires giving false information.

HPI Running a hire purchase check on a car to establish ownership. Illegal? No.

Mob Conv Finding out to whom a mobile phone number is registered. Illegal? Yes.

T/P Obtaining details of phone bills. Illegal? Yes: requires giving false information.

Veh Reg Establishing ownership of a vehicle from its number plate. Illegal? Yes.

XD Obtaining an ex-directory number. Illegal? Yes.