The 200,000 abused figure is wobbly

Rob MacCulloch writes:

Let’s take a look at the Royal Commission report. It turns out that the Commission never estimated the number who’ve suffered abuse to be 200,000. That number was featured in Chapter 5 of its report, called “The Extent of Abuse and Neglect in State Care”. It contains little original research & instead “largely relies on research by private Wellington consultants Martin Jenkins (MJ)” in 2020. The Commission states Martin Jenkins “provided low & high estimates of 114,000 and 256,000, respectively, for how many people may have been abused or neglected”. However, the MJ report does not state that 114,000 is their low estimate. …

Using ‘top down’, the number of abused ranges from a low of 114,000 to a high of 256,000. As these numbers are so abjectly unreliable, MJ use another approach, called ‘bottom up’, that takes actual reports of abuse (which are low, averaging less than 1% from 1950 to 2019) and multiplies them by a factor of up to 10 based on international crime surveys, as well as NZ surveys (taking a view that under-reporting is of this magnitude). Who knows what is the true factor? Why use overseas studies?

Using ‘bottom up’, the new estimate ranges from a low of 36,000 to a high of 65,000. (See Figure 15 on page 46 for a summary). The numbers calculated using these two different approaches are wildly different. So MJ did not report a “low estimate” of 114,000, as claimed yesterday by the Commission. It was 36,000.

14k to 256K with 36,000 is still a horrendously high figure, but of course far less than 200,000. What we have is a range of 36k to 65k using one method and another. And of course both are based on assumptions that are contestable.

This should not be used to minimise the impact on those abused, but is is a caution about not just taking a headline number as meaningful.