The £20 million scheme would provide compensation for thousands of children who suffered abuse in residential institutions between 1922–95 — however, campaigners say the redress scheme would save taxpayers “at least £10 million” compared to the costs of compensation.

The costs are detailed in a report commissioned from Quarter Chartered Accountants by the Panel of Experts on Redress, made up of survivor groups, individual survivors, academics, lawyers, human rights organisations, practitioners and experts.

They propose survivors receive a common experience payment of at least £10,000, calculated on time spent in an institution and an individual assessment of mental, physical and sexual abuse suffered.

The model compensation scheme is based on wide consultation with survivors and analysis of redress schemes in other jurisdictions.

Based on a figure of 524 eligible victims – the number of survivors who made applications to the Historic Institutional Abuse Inquiry – and the likely level of compensation awards, the accountants have calculated that the scheme would cost just over £20 million.

Litigation by the same number of victims through the civil claims in the courts would cost £10 million more, and a much higher proportion of the overall costs would be eaten up in legal fees.

It is unclear how many victims will be eligible for compensation until Sir Anthony Hart completes the Inquiry report in January 2017.

Speaking outside Stormont, Margaret McGuckin of Survivors and Victims of Institutional Abuse (SAVIA) said: “Redress is a practical way for government and others to say sorry for how badly they let us down as children.

“We suffered then and have suffered the consequences through our lives ever since – psychological damage and lost opportunities. We shouldn’t have to suffer on into our old age as well.”