Under new rules introduced on Monday, many shoppers in England will be charged 5p to use a plastic bag.
The hope is that the new bag levy will be enough to encourage consumers to bring their own carrier and, ultimately, dramatically reduce the 7.6 billion plastic bags used in England each year. Similar legislation in Wales and Northern Ireland has seen a near 80% reduction in plastic bag use since 2010.
Early indications, however, suggest that the Government’s high profile behaviour change campaign ignores much of the latest thinking from behavioural science and is likely to be less effective as a result.
Firstly, the relative complexity of England’s new rules are likely to cause confusion among retailers and customers alike.
Shops with more than 250 employees – large retailers like Tesco, Sainsbury’s and Top Shop – must charge 5p per bag. However, smaller retailers are exempt from the rule. Similarly, carrier bags remain free for people buying uncooked meat, loose vegetables and, of all things, knives, axes and razor blades. And there have also been warnings about the bacteria risks of reusing bags, particularly when the bag is reused for different purposes.
One of the key lessons from successful behavioural based interventions is to make it easy. The new plastic bag rules seem anything but simple.
Secondly, there are big question marks over the effectiveness of economic incentives – or in this case disincentives – alone.
Charges can hit people in the pocket and make them think twice before incurring avoidable costs. But it is debatable whether 5p a bag is a high enough levy. While there are major discrepancies across the English regions, median income in England is higher than in Wales, Northern Ireland and Scotland.
Campaigners are already calling for England to follow the Republic of Ireland and charge at least 10p per bag in an attempt to make the charge more noticeable.
Similarly, incentives can be counterproductive and provide a justification for undesired actions – in this case, I’ve paid my ‘tax’ for my actions, so it’s okay to behave in the same way. For incentives to work effectively, they often need to be combined with other techniques that are attuned to how people think and make decisions. For example, a better explanation of the impact of ‘bad’ behaviour and the losses which we, as individuals and family members, may incur.
It’s also important to reinforce good behaviour as well as penalise bad for interventions to be effective. Sadly, some retailers have already used the new bag charge to remove previous rewards. For example, Tesco no longer offers additional ‘green points’ on their Clubcard for shoppers who use their own bags.
This brings us neatly on to the third area where the new initiative could learn the lessons from behavioural science – namely testing what works before introducing a mass roll-out.
Yes, the bag levy has worked in Northern Ireland and Wales. But the impact has been much less pronounced in Scotland. There’s an argument that a number of different behavioural change techniques could have been tested before introducing the relatively blunt tool of legislation – a thoughtful nudge as well as a shove to try and engage even the most entrenched plastic carrier abuser.
There is considerable merit in the new laws and they are likely to have a significant impact. But, unless we apply the latest thinking from behavioural science, wholesale behaviour change may not be quite in the bag.