Officials from the Care Quality Commission will face questions from a Health Select Committee over an alleged cover up into the deaths of mothers and babies at Furness General Hospital.
Bosses at the crisis-hit health regulator admitted today that they "got it wrong" when they omitted the names of senior executives alleged to be involved in the cover-up of a critical report.
The Care Quality Commission's (CQC's) latest report detailed how officials might have suppressed a damning internal review into its inspections at Furness General Hospital.
The critical report said the body failed to properly investigate University Hospitals of Morecambe Bay NHS Foundation Trust, which runs the hospital where a number of mothers and babies died.
Three senior executives - former chief executive Cynthia Bower, her deputy Jill Finney and media manager Anna Jefferson - have been accused of agreeing that the report should be deleted, which they have strenuously denied.
But when the independent report into the alleged cover-up was first published, the names of the trio were redacted - a move made after the CQC received legal advice suggesting that publishing the names could breach data protection laws.
Amid mounting pressure to name those involved, officials sought new legal advice and decided to publish the names.
Appearing before the Health Select Committee, CQC chairman David Prior said he "regretted" the error, adding: "I got that call completely wrong. I accept that criticism."
Chief executive David Behan said: "I made the decision. I clearly got that wrong."
Ms Bower and Ms Jefferson are alleged to have "verbally agreed" to cover up the internal report under the instruction of Ms Finney because it was "potentially damaging to the CQC's reputation".
Mr Prior said: "I really bitterly regret that mistake. The presumption in the CQC now is that we will always publish unless there is an overpowering reason why we shouldn't.
"We got it wrong and there is no point hiding behind legal advice. We should have put the names out straight away and we didn't."
Mr Prior said the new report, written by management consultants Grant Thornton, provided "strong evidence" of a cover-up.
He said: "This report is a damning indictment of CQC. It outlines incompetence, complacency, dysfunction. It shows a culture of suppression and oppression.
"It described an organisation that was not fit for purpose. It also revealed very strong evidence of a cover-up of a document. A meeting took place, a paper was produced about addressing some very serious issues about Morecambe Bay, and then that paper disappeared. That is very strong evidence to me of suppression.
"CQC was more interested in protecting its own reputation than it was putting out the truth.
"Of course, the paradox of this was that had they published this document, or taken it to the board, people would have thought 'They are being honest about themselves' and actually their reputation would have benefited from that honesty. The act of covering up does far more damage than the underlying document."
He added that to "deliberately bury" an important document is "madness".
Mr Prior pledged a culture of openness and transparency in the regulator in the future, adding: "Going forward, we will be a radically different organisation."
He said that in September the organisation will publish a list of all hospitals that it is concerned about.