Towards a better understanding of people's perception of fairness through comparing socio-economic with spatial explanations: a residents’ survey on public acceptability of the London ULEZ


  • Thomas Verbeek TU Delft


environmental justice, transport justice, fairness, public acceptability, just sustainability




The growing evidence on the health impact of exposure to air pollution, heightened public concern and stricter environmental legislation make local governments adopt increasingly strict measures to improve urban air quality. A popular instrument is the Low Emission Zone (LEZ), a defined urban area where the most polluting vehicles are no longer welcome. Although several studies have shown a significant (small) reduction in pollution levels after implementation, the policy measure remains controversial.

The controversy is explained by two dimensions of social justice that can come into conflict when implementing this measure: environmental justice (Walker, 2012) and transport justice (Martens, 2016). Supporters of LEZs often use environmental justice arguments based on the principle that everyone has the right to a healthy environment, including clean air. They think it is a fair “polluter pays” instrument that benefits more deprived communities in particular, because they are more exposed and contribute less to air pollution. Opponents of LEZs often use transport justice arguments based on the principle that everyone has the right to a minimal access to an adequate transport network, because accessibility is essential for social inclusion. They fear an unequal access to different transport options and disproportional financial burdens on disadvantaged socio-economic groups.

This conflict leads to a just sustainability dilemma: what is a “fair” or “just” balance when looking at policy instruments that have positive and negative effects across different domains, touching on collective values and individual aspirations? According to the work of political theorists, universalism should not be prioritised above the local and plural when considering justice and fairness (Schlosberg, 2009) and criteria will differ according to how we value things in a certain place and time (Walzer, 1983). However, we can still learn from local case studies to operationalise fairness and develop socially acceptable rules.

In this paper the results will be presented of a survey with approximately 1,000 Greater London residents. London is a leading city in implementing LEZs, having introduced an initial central Ultra Low Emission Zone (ULEZ) in 2019, which significantly expanded in autumn 2021 to cover an area of 381 km2. The survey was carried out in summer 2022, after this expansion, when there was vigorous debate on a further expansion to cover all of Greater London (1,569 km2), which eventually happened in Summer 2023. This period provides an interesting backdrop for a survey on public acceptability and perception of fairness of the instrument. By associating the postcode-based location of responses with individual socio-economic and demographic characteristics collected through the survey, we analyse whether socio-economic characteristics (such as education and income) or residential location (determining how one is impacted by the measure) are more important to explain acceptability and perception of fairness. This people-driven perspective can help to develop the right mitigation and support measures, either based on location or socio-economic group. This can inspire other cities in adopting fair urban air quality management strategies, and provide valuable input for operationalisation of just transition policies in general.


Martens, K. (2016) Transport justice: Designing fair transportation systems. London: Routledge.

Schlosberg, D. (2009) Defining Environmental Justice: Theories, Movements, and Nature. Oxford: Oxford University Press.

Verbeek, T. & Hincks, S. (2022) ‘The ‘just’ management of urban air pollution? A geospatial analysis of low emission zones in Brussels and London’, Applied Geography, 140, 102642.

Walker, G. (2012) Environmental justice: concepts, evidence and politics. London: Routledge.

Walzer, M. (1983) Spheres of Justice: A Defense of Pluralism and Equality. New York: Basic Books.