Blog: The plastic bag levy – a missed opportunity for behavioural change

Since early October, retailers in England have been required to charge customers 5p for every plastic bag they use. Similar legislation is already in place in the rest of the United Kingdom, where it has been highly successful in reducing the number of bags used; in Wales, shops hand out 71% fewer bags now than they did before the levy was introduced in 2011, and in Scotland the number is down 80% in just a single year.

Although the levy introduced in England is unlikely to be quite as successful as these examples, primarily because it does not extend to SME’s, it is still bound to reduce plastic bag use by a significant amount, without costing much or introducing major bureaucratic burdens.

The policy is welcome but it is also a missed opportunity to spark greater shifts in consumer behaviour and a wider conversation about consumption and wastefulness.

Behavioural psychologists describe the phenomenon of ‘spillover effects’ where engaging in one activity affects the likelihood of engaging in another. One such effect is called ‘the foot in the door’ effect: individuals who have already agreed to an initial small request are more likely to agree to a subsequent, larger, request. The classic example of this is an experiment in which homeowners in California were initially asked to display a small sticker in their car or window urging safe driving, and then subsequently asked to place a large sign in their front lawn.

Individuals who were asked to put the sign in their lawn without previously being asked to display the sticker had a relatively low rate of ‘compliance’. Individuals who were asked to display the sticker urging safe driving and then subsequently asked to display a sign with a different message (to ‘Keep California Beautiful’) had significantly higher rates of compliance. When the sticker and the sign both urged similar behaviour, compliance increased again (though by a much smaller margin).

In explaining this shift, the researchers suggested that agreeing to the first request might help to induce an attitudinal shift in an individual. Having started to think of themselves as ‘the kind of person who does this sort of thing’, their later action is more likely to be consistent with this self-perception. Having said which, spillovers can be negative as well as positive (such as in the cases of moral licensing, where I allow myself to eat an entire packet of biscuits as a reward for going for a short run), and in any real world scenario there are other behaviours, desires, and impulses which may take precedence.

Some people are wary of applying behavioural insights to policy making but since 2010 the government has no such qualms, setting up and growing the Behavioural Impact Unit (whose founder David Halpern recently spoke at the RSA. Its work shows how small re-calibrations of the choices presented to individuals can yield significant behavioural change.

Given this, the introduction of the plastic bag levy could surely have been an opportunity to catalyse wider change. Instead of not using or reusing plastic bags being seen primarily as a cost-avoidance measure by consumers introducing the policy with an unashamed tone of environmentalism and celebrating the possible emergence of new green behaviours may have cultivated different attitudinal change. It could have helped lead people to see themselves as green consumers (or, at least, not wasteful). This attitudinal change could then have yielded additional pro-environmental behaviours, either through support for further government action (such as a drive to reduce plastic in food packaging) or voluntary corporate or consumer action.

The levy could also have prompted a civic conversation about consumption more broadly. Indeed the latent potential of the levy as a catalyst for a re-thinking of our approach to consumption outweighs its direct environmental worth.

These conversations are already happening; the RSA’s Great Recovery Project is an excellent example of how approaching these issues in the context of design can energise people to think not only about their own consumption, but about material flows through society as a whole. Unfortunately, these discussions have yet to break into the public sphere for a sustained period of time.

Given the Government’s enthusiasm for using behavioural science in public policy, their reluctance to do so in the context of the levy might seem surprising. Unfortunately, it does seem consistent with their approach to environmental issues since the election, with cuts to subsidies for renewable energy, abolition of zero-carbon standards for new houses, and reduced incentives to drive fuel-efficient cars. It is the government’s lack of commitment to tackling environmental problems, rather than an antipathy towards the use of behavioural methodologies in public policy that provides the best explanation for this wasted chance.

The plastic bag levy is therefore merely a good one off initiative rather than an element in a much needed broader strategy for environmental behaviour change.