Bereaved families have said lives were "undoubtedly put at risk" when a health regulator ignored information supplied to it by the police about practising midwives.
The comments come after a "damning" report was released about the Nursing and Midwifery Council's handling of the cases of midwives involved in the Morecambe Bay scandal.
Major care failures were linked to at least 12 deaths of mothers and babies at Furness General Hospital between 2004 and 2012.
Poor record keeping, mishandling of bereaved families and lengthy and delayed investigations all feature in the report by the Professional Standards Authority.
The report also reveals how the NMC failed to act on information provided by the police for almost two years - which highlighted concerns about the midwives they believed should be investigated.
We were really concerned that reports of the same midwives who we had the cases sitting in front of us were still practising at the hospital.
Prior to the report being released, the head of the NMC quit her role. Jackie Smith announced she was stepping down as chief executive and registrar on Monday.
Concerns at the hospital were first raised after the death of nine-day-old Joshua Titcombe in 2008 from sepsis.
Joshua's father James Titcombe gave a joint statement with other families affected by the scandal. He, Liza Brady and Carl Hendrickson said the scale of failures was "truly shocking".
"The NMC have been defensive, legalistic and in some cases, grossly misleading in their responses to families and others. This culture of denial and reputational management is reminiscent of the very worst of the culture our families have experienced over the years."
The NMC has admitted that its handling of the Morecambe Bay cases was "unacceptable" and has apologised.
The former head of the NMC said: "The NMC's approach to the Morecambe Bay cases - in particular the way we communicated with the families - was unacceptable and I am truly sorry for this.
"We take the findings of this review extremely seriously and we're committed to improving the way we communicate with families, witnesses and all those involved in the fitness to practise process.
Since 2014 we've made significant changes to improve the way we work and as the report recognises, we're now a very different organisation. The changes we've made puts vulnerable witnesses and families affected by failings in care at the heart of our work. But we know that there is much more to do.