A cautionary tale of legionella and hysteria

 

A note appeared on the tap in the kitchen area of our departmental common room: ‘do not use’. This made the usual arrangement for washing up cups of tea and coffee etc. impossible in this room, caused unwashed crockery to pile up, and caused a little annoyance and frustration. Eventually, I managed to speak to a plumber involved in dealing with the tap. He explained that the ‘clean water people’ had left the note because of possible legionella. He also said that the explanation was not provided on the note ‘to avoid hysteria’ in members of staff who would see it. It’s the classic ‘don’t tell the public about the threat as they’ll only panic’ scenario. Those with the information on a possible threat think that the public will overreact or be subject to undue fear if they learn of the threat. Therefore, they restrict that information – in this case they leave the note without mentioning legionella. But the real risk – in this case as in many examples of restricting information to avoid public ‘panic’ -- is not unwarranted fear. Rather it is the public not realising the danger. Not realising that legionella is involved in the tap situation, which is also present in contaminated aerosols or mist (which can be inhaled), could easily lead to staff members touching the tap, running the water, standing too close to running water and so on. The real danger in many emergencies is not panic, but not realizing that it's an emergency. So trust the public with the truth.

20 years since the London bombings -- a new way to think about resilience

 

On this day 20 years ago, I was with @ChrisCocking and Steve Reicher at the Royal Society summer exhibition in London, presenting our work on how people behave in emergency evacuations. As I tried to travel to the exhibition venue, I was part of a crowd of grumbling commuters ordered off tube trains because of what we later discovered was a terrorist attack on three trains and a bus. It was surreal to walk across London during rush hour that morning and see so many others doing the same, as the tube system was completely closed down.

Later, we spoke to survivors and in the end gathered dozens of accounts of what people in those bombed trains saw, did and experienced. The study was important, not only for being a further riposte to the idea of public ‘panic’, but also because it prompted us to think in a new way about resilience.

The Civil Contingencies Act had just come in (2004), and there was now an official recognition that the public could – indeed had to – play a role in emergency response. But in the main, this public capacity for resilience was understood in the guidance as based on social capital or existing relationships. It was also understood officially as less agentic than that of the authorities. The new way of thinking about collective resilience was based on the social identity approach. Those caught up in the London bombings case were commuters, and so were strangers to each other.

Yet our interviewees described how after the bombs had exploded there was a sense of ‘we-ness’ with these strangers. They became a psychological group, based on their common situation. That groupness drove mutually supportive behaviours – sharing bottles of water, physically lifting others, tying tourniquets.

It allowed them to coordinate – for example in removing train doors as well as in filing out in an orderly way as they evacuated. The survivors were left alone for more than 15 minutes before the professionals reached them, but they had become the zero responders, providing emotional support and saving lives.

Read more here:

@ukri.org funded

 https://sus-udd.dk/wp-content/uploads/2025/01/Drury-et-al.-2009-London-bombings-of-2005.pdf  

Six zombie ideas in crowd psychology

 

What are zombie ideas? These are ideas that keep coming back, even though they have been thoroughly refuted by the evidence. They should be dead, but they won’t stay dead! They keep coming back because they serve certain interests or prejudices (or both). Here are six zombie ideas in crowd psychology that keep cropping up in everyday talk, in the news, among policymakers and practitioners, and in academic publications. And here’s why they’re wrong.

1. De-individuation

The most distinctive claim in the ‘de-individuation’ family of theories was inherited from Gustave Le Bon – the idea that being anonymous leads to a loss of self and hence uncontrolled, anti-normative behaviour. This idea could not cope with the evidence that conditions of anonymity in fact are associated with a wide range of behaviours, including accentuation of pro-social behaviours. There is little evidence that anonymity leads to a ‘de-individuated’ state of reduced private self-awareness. Rather, anonymity makes group identities more salient and hence leads to more, not less, conformity to relevant situational norms.

Key reading: Postmes & Spears (1998)

Gustave Le Bon headstone

(Pierre-Yves Beaudouin / Wikimedia Commons / CC BY-SA 4.0)

2. Groupthink

While groupthink is supposedly a pitfall of small groups and organizations rather than crowds, I include it here as it’s another example of an anti-collectivist concept. It is used loosely by commentators to refer to any situation where group members prioritise the group’s own ideas over critical or external views. For example, some of those involved in decision-making at the height of the Covid pandemic have used the idea of groupthink to explain organizational failures in decision-making. The distinctive claim of the ‘groupthink’ concept is that highly cohesive groups will be subject to concurrence-seeking at the expense of critical inquiry, leading to faulty decisions. A big problem for this idea is that there is not much evidence that greater cohesiveness leads to worse decision-making. Rather than the tendency to ignore critical evidence being a function of groupness, it’s more likely to be an effect of particular group norms (for example that value loyalty).

Key reading: Aldag (2022)

3. Mass panic

Aside from the profound problems of judging whether behaviour counts as ‘panic’ in an emergency (what is reasonable behaviour in this situation?) and the related problem of trying to import a polysemic everyday term into scientific explanation, there is another basic problem. There is no evidence that people in crowds are typically uncontrolled, selfish or competitive in emergencies. The common finding of social support among people in emergencies adds to the problems of this concept.

Key reading: Clarke (2002)

4. Contagion

One of the most popular concepts in the social and behavioural sciences, ‘contagion’ is often used synonymously with spread and social influence. But there is little evidence that mere exposure alone is sufficient to prompt emulation. Group boundaries in the transmission of behaviours and emotions demonstrate this. Even for supposedly basic processes like so-called emotional contagion, reviews of the evidence suggest that the mimicry involved is not automatic, but rather relates to communication goals that already involve an emotional orientation to the other person.

Key reading: Drury et al. (2019)

5. The hooligan

The hooligan is a concept from sociology more than psychology, but it is a good example of a dispositional explanation. For the earliest beginnings of crowd psychology as a science, some have claimed that crowd conflict occurs through the convergence of certain kinds of individuals (usually with criminal, violent, or poorly socialized dispositions). From the 1960s urban riots in the USA to the 2011 English riots, proponents of such ideas have failed to produce the required evidence. In the football context, of course some groups seek conflict, but this in itself can’t explain collective behaviour. As Stott and Pearson explain, the 'hooligan' concept has little explanatory power: ‘disorder’ sometimes occurs when known ‘hooligans’ are not present; and when known ‘hooligans’ are present, ‘disorder’ doesn’t always take place.

Key reading: Pearson & Stott (2022)

6. Mob mentality

An overarching zombie idea, that links many of the above, but which also includes the distinctive claims that in crowds people revert to a simpler, less intelligent, and more primitive or archaic psychology, under the influence of which behaviour tends to gullibility, barbarism, loss of control, and violence. The fundamental problem here is two-fold. First, if this is a real tendency it cannot easily explain the majority of crowds, which are peaceful and pro-social. Second, the suggestion of a universal tendency like this cannot explain the social form of behaviour when there is crowd violence. To explain the distinct targets of the sans culottes, urban rioters, football fans and many others, and the sophistication in even the most violent crowd, it makes better sense to refer to their identities, group norms, and values.

Key reading: Reicher (1984)

Understanding collective flight responses to (mis)perceived hostile threats in Britain 2010-2019: a systematic review of ten years of false alarms in crowded spaces

Understanding collective flight responses to (mis)perceived hostile threats in Britain 2010-2019: a systematic review of ten years of false alarms in crowded spaces: (2022). Understanding collective flight responses to (mis)perceived hostile threats in Britain 2010-2019: a systematic review of ten years of false alarms in crowded spaces. Journal of Risk Research.