Mental health chiefs have been told to carry out an urgent review of how serious incidents are reported in its facilities.
The call, contained in two reports out yesterday, came as new figures showed the number of unexpected deaths recorded by the Norfolk and Suffolk NHS Foundation Trust (NSFT) has almost doubled over the last three years.
Trust bosses say they are already acting on the recommendations made in the investigations.
But campaigners say the findings support their plea for increased funding of the sector, rather than cuts.
It emerged yesterday that a total of 157 unexpected deaths had been recorded by the trust in 2015-16.
The figure is an increase of 18 on the previous year and compares to 88 in 2012-13.
In February, the NSFT commissioned Verita to carry out an independent inquiry into the numbers of unexpected deaths of people in its care, following widespread public concern about the issue.
Its report contains 13 recommendations for improved practices and training for working with bereaved families.
At the same time, NHS England carried out its own review, which said: “The review of the policies associated with incident reporting and requirements of duty of candour highlighted that they require urgent updating to bring them in line with the new Serious Incident framework.”
But Verita also said the figures were likely to be affected by the trust’s early reporting policy, while a lack of national data meant meaningful comparisons could not be made to other trusts.
Trust chief executive Michael Scott said: “All of the recommendations made by Verita and NHS England are already, or will be, acted upon.
“We are far from complacent, and there would be no point in our commissioning this investigation if we turn a blind eye to where it indicates we need to do better. That is something we simply will not do.
“The safety of our service users and our services is paramount and one avoidable death is one too many. That is why we commissioned this investigation. We wanted to ensure that our services are as safe as they can possibly be.”
However, campaigners who have compiled a petition calling for King’s Lynn’s Fermoy unit to be saved from potential closure, say the figures highlight the extent of the problems.
Officials from the North West Norfolk constituency Labour party presented the petition, which contains more than 450 signatures, to West Norfolk clinical commissioning group (CCG) chairman Dr Ian Mack ahead of its board meeting yesterday morning.
The petition calls for the CCG to give assurances that it would continue to commission services from the unit.
They claim that the CCG spends the smallest proportion of its funding on mental health of any in Norfolk, less than eight per cent.
And party secretary Jo Rust said of the death figures: “This shows we need more funding, not less.”
But Dr Mack insisted its funding decision were in line with parity of esteem guidelines, which require mental health needs to be given the same priority as physical health.
He added: “We are very clear we will continue to support mental health beds in the west.”