Jimmy Savile's victims have called for a single judge-led inquiry into how the disgraced former DJ was able to evade justice for so long.
Alan Collins, the lawyer representing around 60 people who reported being abused by Savile, said he feared an opportunity could be "missed" by all the other investigations into Savile.
He said there should be one inquiry led by a High Court judge with "considerable" experience in criminal law who would have access to all the work undertaken by the other investigations.
"We have a number of inquiries under way at the moment - there must be at least a dozen - we have got the BBC being investigated, the NHS, various hospitals, and... we have the police and Crown Prosecution Service," he told BBC Breakfast.
"There are a lot of inquiries under way at the moment and the concern is, whilst individually they may do an excellent job - reports will come out and will no doubt be extremely useful - the fact is that those who are investigating are not necessarily benefiting from the other investigations, so they are all doing their own thing as it were, and the victims feel that an opportunity may be lost because we really do need to know not just about the extent of Savile's offending - although that is pretty clear.
"It is about really, how and why - how was Savile was able to abuse so many children and young people over so many decades?"
Allegations about Savile, who died in 2011, began to emerge following an ITV expose in October 2012 in which several women said they were abused by him when they were teenagers.
Two separate reports published almost exactly a year ago said Savile was ''a prolific, predatory sex offender'' who could have been prosecuted for offences against at least three victims while he was alive.
The disgraced TV presenter used his celebrity status to ''hide in plain sight'', with 214 criminal offences recorded against him across 28 police forces, a report by Scotland Yard and the NSPCC found.
It also revealed that Savile abused his victims at 14 medical sites including hospitals, mental health units and even a hospice.
The BBC has said its independent inquiry, led by Dame Janet Smith, into what the corporation knew about Savile is due to publish its findings this month.
The NHS is also holding several investigations. Health Secretary Jeremy Hunt announced in November that a further 19 hospitals were now carrying out inquiries into links with Savile.
Speaking to the BBC, Mr Collins said in the 1980s there was a debate within government over whether Savile should be given a knighthood.
"The prime minister at the time, Margaret Thatcher, was quite keen for Savile to be knighted because of his charitable work. The Civil Service was advising her 'hold back' because they were concerned by media reports in the early 1980s about Savile's lifestyle and, in particular, claims apparently made by him about his private life but also about being able to fix things in a not necessarily very pleasant way.
"Those concerns were there and it begs the question why on earth - in the 1980s there were these concerns - Savile was allowed to work in NHS hospitals and appear on BBC television programmes geared to a young audience."