Senior Leicestershire Police officers have remained tight-lipped about their role co-ordinating the search for the toddler since she vanished from a Portuguese holiday resort in May 2007.
But analysts at the force have drawn up a list detailing the mass of information they have gathered and considered whether they would ever release any of it to the general public.
The paperwork includes everything from correspondence with Government ministers, minutes of police meetings, details of leads and sightings to copies of letters from the McCann family.
Leicestershire Police said they will not release any information while the inquiry is ongoing and will never reveal the tactics of their investigation. But internal documents suggest some papers may eventually be published.
They stated: "Anything in relation to the investigation into the disappearance of Madeleine McCann will not be released whilst it remains ongoing.
"Consideration may be given to releasing certain material, ie, that which would not reveal police tactics, when the circumstances surrounding Madeleine's disappearance are fully known and the person/people involved have been brought to justice and a suitable period for any appeal has elapsed."
Madeleine, from Rothley, Leicestershire, disappeared on May 3 2007 from Praia da Luz, nine days before her fourth birthday.
An investigation into her disappearance was carried out by the Portuguese police, supported by Leicestershire Police.
The force is responsible for co-ordinating British inquiries under the codename Operation Task.
in Press Association
From the Leicestershire Police, released on 18th December 2009: Operation Task Publication strategy [PDF file- bellow in images, click to read]
Currently and since June 2008 there isn't any Police force investigating the Madeleine McCann disappearence, be it the Judiciary Portuguese Police, Interpol, Europol, Scotland Yard or Leicestershire Constabulary Police.
The British police, and in particular, Leicestershire Constabulary have no jurisdiction on the so called 'Maddie case' - unless Kate and Gerry McCann decided, finally, to file a missing persons report in that Country.
Nevertheless, for an investigation to be ongoing that would mean that the case was indeed being worked, investigated by proper authorities and that is not the case, the process to Madeleine McCann's disappearence is archived, waiting for better evidence, at the Portuguese Public Ministry.
As many of you have pointed out, the timing for this unnamed [no officer names] and unassigned [no journalists] press release is coincidentally odd, considering that one liaison officer, belonging to the Scotland Yard, who was an element of 'Operation Task', is supposed to be heard as a witness in less than two weeks time at the Civil Court of Lisbon for Mr. Amaral's defense.
Is this a hint, of yet another impediment, similar to the 6 months old rogatory letters that had to be sent various times to the Home Office until they were accepted?