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New York City litter bin
Social and behavioural

Researchers chucked litter on the streets of New York and Bern to see if anyone would intervene

Fieldwork bears out the idea that city inhabitants care enough about their environment to intervene when someone makes it worse… sometimes.

06 December 2016

By Alex Fradera

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To maintain pleasant public spaces requires that we all implicitly agree to certain civil behaviours, like pocketing our chocolate wrappers rather than leaving them strewn on the pavement, or turning the stereo down after eleven. But when these implicit agreements are too frequently ignored they can lose their force entirely, jeopardising the social order. To keep things together, one or more of us need to hold any miscreants to account… but who wants that hassle? A new paper in the journal Rationality and Society explores real-life littering norm enforcers, taking us from the streets of Switzerland to the New York underground.

The sociologists Joël Berger and Debra Hevenstone convened at various crowded city transit stops, and waited for a transit service (a tram in Bern, Switzerland or a New York subway train) to deposit a load of commuters. Then one researcher would perform an act of littering in front of the commuters, tossing an empty bottle near, but not into, a rubbish bin, while the other researcher observed how people responded.

Berger and Hevenstone were particularly interested in whether there would be any instances of social sanctioning – that is, a commuter directly confronting the offending researcher – an act also sometimes labelled "costly punishment", because the individual has to inconvenience themselves to enforce the social rules. Social sanctioning has been studied frequently in laboratory conditions but only rarely in "the wild".

Replicating one of the few examples of previous field research on littering, conducted on the streets of Athens, Berger and Hevenstone found that littering provocations did produce measurable responses in bystanders, although at lower levels than those found in the lab, and that passive-aggressive grumbles outnumbered direct confrontation. The research also revealed two further factors that affected the likelihood of commuter intervention: context and culture.

Any performance needs a set, and in this case the researchers alternated between two: sometimes trashing up the bin's surroundings by arranging refuse bags around it, and in other cases making it as pristine as possible. In grubby surroundings, less than three per cent of littering events were met with a direct challenge – "Are you going to pick that up?" – versus nearly eight per cent in a clean environment. The environment had an even greater influence on whether bystanders tidied up after the loutish experimenter – in 16 per cent of cases when clean, but little more than 1 per cent when grubby. This effect calls to mind the (still controversial) Broken Windows criminology theory, which argues that run-down environments encourage further violations because potential perpetrators reckon their actions will go unpunished. The new research suggests that while violations may go up in run-down environments, challenges to violations may also go down, truly the ingredients for a vicious spiral.

As well as local conditions, cultural factors appeared to play a role. In Switzerland, nearly half of acts were met with some kind of response – a quarter of cases by subtle disapproval (head-shaking or muttering to friends), tidying up in 13 per cent of cases, and a direct intervention in 10 per cent of cases. Meanwhile in New York, the rates were always lower – only a third of cases provoked a reaction, with direct intervention four per cent of the time.

Berger and Hevenstone recount an anecdote: "in Bern, we even had difficulties in maintaining the litter condition. Twice people wanted to remove the bag of garbage. This never happened in NYC." As Bern is a lot smaller than New York, they made another run in larger Zürich to see if it resembled the American city, but the data showed Zürich inhabitants even more likely to tidy up the bottle at 26 per cent, and similar to Bern in rates of direct action (subtle disapproval wasn't measured in this study). The Zürich findings suggest a national tidiness culture rather than a size of city effect.

This fieldwork bears out the idea that city inhabitants care enough about their environment to intervene when someone makes it worse… sometimes. That sometimes becomes a seldom when conditions have already deteriorated. If that applies to your neighbourhood, and you care enough to do something about it, you may need to invest energy to turn things around, so that others become re-engaged with policing the quality of their environment. Sometimes, you need to start with a clean sweep.

Further reading

Norm enforcement in the city revisited: An international field experiment of altruistic punishment, norm maintenance, and broken windows