Hard News by Russell Brown


New Drug Harm Index, new problems

The New Zealand Drug Harm Index 2020 just made it into 2021: it was quietly posted on the Ministry of Health website before Christmas. And it contains some startling claims. Not the least of them, that cannabis is New Zealand's most harmful drug – accounting for $626 million in "community harm" every year. Would you be surprised if I told you more than a third of that was lost GST?

Well, it is: the authors of the index estimate the public purse loses $224 million a year because tax can't be paid on revenue or personal income from producing or selling cannabis. It's nearly all of the foregone tax estimated for illicit drugs in general. If only there was something we could do about that!

The authors acknowledge what you're probably thinking right now, if a little snippily:

Overall, $240.2 million is lost to the tax base through the failure to pay appropriate taxes in relation to revenues and profit generated by illegal drug trafficking. This additional revenue could only be realised either by the legalisation of illegal drugs or by the diversion of this investment into legal forms of investment. Nevertheless, it remains a genuine social harm associated with illegal drug trafficking.

It's only fair to note that (subject to some assumptions about the profitability of selling drugs) this isn't actually wrong and that foregone tax revenue appeared as a harm in the last version of the Index in 2016. It just seems more on the nose after we had a chance to fix it in 2020.

But a similiar similar level of community harm from cannabis, $250 million worth of it, is new. That's the dollar value attributed to "Harm to family and friends". Now, it is laudable that the authors are acknowledging this kind of harm from drug use and seeking to quantify it. But the means of quantifying it is, to put it mildly, questionable.

A significant component of the friends-and-family harm has been calculated not by looking a New Zealand data, but by transposing the findings of this study, which asked people in Nordic countries how much they'd be willing to pay for treatment for someone close to them – a family member or someone they knew well enough to talk to – who had a drug addiction problem. The median responses across all respondents ranged from 500 euros for a friend to 13,000 euros for a child.

The Index authors have then, I think, taken the lower figure of 500 euros and sprayed it across all use of all categories of drugs in New Zealand and added it up in $NZ. Cannabis, because it is so widely used in New Zealand, is then deemed to account for as much harm to friends and family as methamphetamine.

Further, drug use patterns in the Nordic countries and New Zealand are quite different. Notably, mortality from opioid addiction is four or five times higher in those countries, especially in Sweden, where more than half the respondents in the cited study personally knew someone who had been "treated for addiction to illegal drugs". I'm assuming the large majority of them weren't there for cannabis. Indeed, the study's authors suggest it's not very helpful to look at cannabis prevalence in understanding their results.

The Nordic countries study is worthwhile in itself and its authors make some interesting observations, including that harms reported by friends and family are lower in Denmark, where drug use is traditionally "demystified" (in comparison, say, to neo-prohibitionist Sweden). They also say this:

This shows that it is difficult to use expected harm to assess the  actual  level of  harm. It  also  suggests that an important part of the harm of drugs is  related to  fear  and  that the  fear  itself is not well founded. Finally, since  fear  is reduced by experience and closeness, the results imply that one important element in the overall cost of drug use – social fear – may fall if drug use becomes more common in a society.

They seem very conscious of the complexity of what they're measuring. That consciousness has not carried over to the use of their data by the authors of the New Zealand Drug Harm Index, who assume the exact opposite in their report:

The current measure assumed the proportion of the adult population willing to pay for treatment for friend or family was the same in New Zealand as in Norway. This assumption is conservative, as New Zealand’s adult population has a higher proportion of current people who use drugs than Norway’s.

One problem with the Index may be that it has dispensed with the pretty limited form of expert input used in 2016 in assessing the harm posed by individual drugs: "In essence," the authors assure us, "both wastewater analysis and hospital admissions provide the necessary information on a range of illicit drugs."

This may be why they've come up with some plainly ridiculous figures. The serious "personal harm" suffered by heroin users (excluding death) is reported as zero. I guess we can just close all the needle exchanges then! Of course we can't. We know people in New Zealand are still being infected with blood-borne diseases and suffering serious injection injuries and poisonings.

A Drug Harm Index that can fail to detect real, reported, literally costly harm in this way has real problems. But this exercise has been defined by its problems from the beginning. The first attempt, undertaken by Police, counted the cost of enforcement in its dollar figure for harm – meaning, absurdly, that the more harm there was, the more needed to be spent on enforcement, which would duly increase the measured amount of harm. And so on.

Responsibility for the Index was subsequently transferred to the Ministry of Health, whose attempt was better, but committed the fundamental error of conflating harms from natural and synthetic cannabis. This new version still does that to an extent, where hospital admission codings refer only to "cannabinoids". Basically, there's a problem with nearly every measure relating to cannabis.

The authors are also obliged to perform something of a fudge on hospital admissions where, say, someone gets in a fight or injures themselves while blind drunk, but is also found to have cannabis or other illicit drugs on board. Such multiple-cause admissions "were distributed equally over known factors to avoid double-counting". But alcohol harm isn't counted even where it might be the primary cause, because alcohol and tobacco are excluded from the Drug Harm Index.

I'm honestly wondering whether these indexes are worth persisting with, at least in their current form, which were established, with those eye-popping dollar values, as essentially a Police PR exercise.

Let's not deny for a second that drug use can be harmful: that harm is the very thing that drug policy should seek to address. But the Index variously overstates, understates, misattributes or omits various harms through its methodology. Until we can find a way to go out and learn about harm, especially from – crazy, I know – people who use drugs, this is nothing like a policy tool.

Until then, I think there's probably a case for calling it the Prohibition Harm Index.

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