Players' union chief Damian Hopley has reacted in fury and disbelief at the 'disgraceful' leaking of confidential England World Cup Review reports in The Times.
Details from the reports - including anonymous input from the England players who took part in the disastrous campaign in New Zealand - were reported in the newspaper on Wednesday.
Rugby Players Association chief executive Hopley said: "I am absolutely devastated that our RPA members' trust has been so publicly betrayed. Players voluntarily took part in these interviews and gave their honest and frank assessment of England's Rugby World Cup Campaign.
"The aim was to be completely open and transparent and players should be respected for refusing to shy away from some of the problems encountered.
"Players were critical of themselves, of the coaching team and of the RFU and its leadership. Their determination was for everyone to be accountable and take responsibility for the disappointing showing in the Rugby World Cup.
"Many comments were understandably robust because they knew England had not performed as they could have and the players are committed to getting things right for the future."
What particularly angers Hopley is the betrayal of trust after his members were assured that their feedback would be totally confidential.
He added: "Yet no sooner has the report been sent to the Board Members than it appears in a national newspaper.
"If England wants to regain its status as a respected rugby nation, it is imperative that we stop the rot at the top of the game and show some much needed integrity. What example does this set to the game? It is an absolute disgrace.
"It was the lack of faith in the system and process being confidential that saw many players shy away from completing the RFU questionnaires in the first place and, perhaps not surprisingly, their mistrust has been proven to be correct.
"We cannot ignore that once again there has been a serious breach of confidentiality. We are demanding a detailed investigation to track down the source of the leak and deal appropriately with that person.
"If we are serious about destroying the porous culture in our game, then we need to introduce tougher security measures to weed out these self-serving people once and for all."