Our study on the radical flank effect published in Nature Sustainability!

We are excited to share that our study on the radical flank effect has now been published in Nature Sustainability, a leading journal on climate and environmental issues.

People interested in social movements have long-hypothesised about a so-called radical flank effect, whereby radical factions of a movement can improve people’s attitudes towards more moderate factions. Using data from a highly publicised protest campaign by Just Stop Oil (the November 2022 M25 blockade), we sought to test this hypothesis, investigating whether the blockade affected people’s attitudes towards the well known moderate group Friends of the Earth. Read the full paper here, or you can find a shorter research briefing here.

Key findings

We conducted a longitudinal, nationally representative survey before and after a disruptive protest by Just Stop Oil (November 2022). The protests involved activists climbing onto overhead gantries along the M25 motorway, causing significant traffic disruptions and receiving substantial media attention. In line with a positive radical flank effect, we saw that the more people’s awareness of JSO increased from before to after the protests, the more their identification with and support for Friends of the Earth increased. This suggests that while radical tactics may be unpopular, they can benefit the broader movement by sparking large-scale media attention and by giving moderates a boost. Moderate groups could capitalise on this effect by coordinating their activities with those of radical groups to increase public backing and participation.

Our paper builds on two recent experimental studies by Simpson et al. (2023) and Dasch et al. (2024) finding very similar results. The novelty of our study lies in the fact that it used real-world data on a nationally representative sample in the context of a highly mediatised protest rather than relying solely on experimental data. It's an important step forward in validating the radical flank effect in real-world contexts. Controlled experiments are useful, but they can lack ecological validity and be highly artificial—our study addressed that concern.

Beyond the radical flank effect that pertains to the effects of disruptive tactics on other groups, we also investigated effects on people’s support for climate policies. Here, we saw no overall effect. However, those people with low climate concern were negatively affected by the protests, whereas people with higher degrees of climate concern were not. 

Overall, our paper sheds light on the dynamics within social movements and suggests that disruptive protests constitute an untapped strategic resource that moderate groups can leverage by timing their activities to the peaks in attention and momentum that more radical groups create. 

If you’re interested in learning more about the radical flank effect and how it affects the overall balance of pros and cons of disruptive tactics, read the full article here.

If you have any questions or would like to discuss this research further, please don’t hesitate to reach out to us.