Why you shouldn’t always ‘follow the science’

Fairly early in the pandemic it was widely accepted in scientific circles that the likelihood of outdoor transmission of Covid at low-density events — say garden parties or beer gardens — was relatively low.

It might therefore have seemed logical to allow such gatherings to take place sooner than we did. From a practical point of view, however, it could have been a terrible move. As is so often the case, a straightforward scientific finding does not always translate into practical legislation. Like the saying goes: ‘In theory there is no difference between theory and practice, but in practice there is.’ In reality, policy-makers cannot simply follow the science: there is always something else at work.

Here two confounding factors are human behaviour and weather. Had we allowed socialising in gardens, it is likely many such events would have continued into the early evening when it began to get cold. Or, this being Britain, it would have started raining. There is also social convention to contend with: few men and fewer women are content to pee in any garden smaller than an acre. (The acre is a medieval unit of area denoting the minimum size of a plot of land in which it is always permissible to urinate.)

What this means is that, at some point in any outdoor party, two party-goers would inevitably have moved, shivering, to the conservatory, and five more would have needed the loo. An hour later, following a general migration indoors, what started as an outdoor gathering would have morphed into an indoor superspreading event. Something like this seems to have happened at the White House. Any garden party is effectively a house party in the making.

Lawmaking is always part-science, part-craft. During the fuel shortage, several people proposed imposing not a maximum allocation of petrol or diesel per person but a minimum spend. The logic was sound. If there was a minimum charge of £50 at any petrol station, only those genuinely low on fuel would have the spare tank capacity to fill up, meaning that people with part-full tanks who were simply stockpiling fuel out of expediency would pay heavily for the privilege.

The problem is perceived fairness. It would give 4x4 owners with huge tanks an unfair advantage, and penalise the cash-constrained. Outside the richer parts of Britain, most people do not fill their tanks completely, but top up a fraction of a tank at a time to aid cashflow. This partly explains the rapid onset of the crisis.

Interestingly, however, the same principle might work for electric car chargers. The reason is that electric car chargers ‘know’ the level of charge of the battery they are charging. Hence if you have a bank of four rapid car chargers and three are in use, you could reserve the fourth for drivers whose battery is at 25 per cent or below. It could charge to only 50 per cent unless another bay became free in the meantime. This would reduce the fear that you might arrive at a charging station in desperation to find it fully in use by people charging to 90 per cent. Unlike petrol pumps, electric chargers might be intelligent enough to impose rationing fairly. We need a few more ideas like this. Even in Britain, electric-car owners have yet to devise a system of queuing —the equivalent of putting coins on the edge of a pool table.

Christmas will be an interesting test for Britain’s electric car--charging infrastructure, with many people undertaking long journeys simultaneously. Expect tabloid stories about ‘charger rage’. But this is yet another case where technology — like pandemics — proceeds at a far greater pace than our ability to conceive and implement intelligent rules and conventions in response.