Urban tracer dispersion experiment in London (DAPPLE) 2003: field study and comparison with empirical prediction

The DAPPLE (Dispersion of Air Pollutants and their Penetration into the Local Environment) project seeks to characterise near-field urban atmospheric dispersion using a multidisciplinary approach. In this paper we report on the first tracer dispersion experiment carried out in May 2003. Results of concurrent meteorological measurements are presented. Variations of receptor tracer concentration with time are presented. Meteorological observations suggest that in-street channelling and flow-switching at intersections take place. A comparison between roof top and surface measurements suggest that rapid vertical mixing occurs, and a comparison between a simple dispersion model and maximum concentrations observed are presented

Urban tracer dispersion experiments during the second DAPPLE field campaign in London 2004

As part of the DAPPLE programme two large scale urban tracer experiments using multiple simultaneous releases of cyclic perfluoroalkanes from fixed location point sources was performed. The receptor concentrations along with relevant meteorological parameters measured are compared with a three screening dispersion models in order to best predict the decay of pollution sources with respect to distance. It is shown here that the simple dispersion models tested here can provide a reasonable upper bound estimate of the maximum concentrations measured with an empirical model derived from field observations and wind tunnel studies providing the best estimate. An indoor receptor was also used to assess indoor concentrations and their pertinence to commonly used evacuation procedures.

Envy, facts and justice: a critique of the treatment of envy in justice as fairness

A common anti-egalitarian argument is that equality is motivated by envy, or the desire to placate envy. In order to avoid this charge, John Rawls explicitly banishes envy from his original position. This article argues that this is an inconsistent and untenable position for Rawls, as he treats envy as if it were a fact of human psychology and believes that principles of justice should be based on such facts. Therefore envy should be known about in the original position. The consequences for Rawlsian theory—both substantive and methodological—are discussed.

Internal doubts about Cohen's Rescue of Justice

G.A. Cohen's Rescuing Justice and Equality is the culmination of twenty years' work on Rawls's theory of justice. In this paper I distinguish three prongs of attack advanced by Cohen, and show how two of the prongs (the claim that egalitarianism includes productive demands and the claim that equality is best understood as 'luck egalitarianism') are incompatible.

Should we be utopophobes about democracy in particular?

In his book Democratic Authority, David Estlund puts forward a case for democracy, which he labels epistemic proceduralism, that relies on democracy's ability to produce good – that is, substantively just – results. Alongside this case for democracy Estlund attacks what he labels ‘utopophobia’, an aversion to idealistic political theory. In this article I make two points. The first is a general point about what the correct level of ‘idealisation’ is in political theory. Various debates are emerging on this question and, to the extent that they are focused on ‘political theory’ as a whole, I argue, they are flawed. This is because there are different kinds of political concept, and they require different kinds of ideal. My second point is about democracy in particular. If we understand democracy as Estlund does, then we should see it as a problem-solving concept – the problem being that we need coercive institutions and rules, but we do not know what justice requires. As democracy is a response to a problem, we should not allow our theories of it, even at the ideal level, to be too idealised – they must be embedded in the nature of the problem they are to solve, and the beings that have it.

Extending the golden thread? Criminalisation and the presumption of innocence

It seems to be widely accepted that the presumption of innocence, and the attendant standard of 'beyond reasonable doubt' properly apply in the courtroom as a procedural principle directly grounded in the moral imperative to avoid punishing those who should not be punished. In this article I argue that if this is correct, then we ought be as careful about what we criminalise, as we are about who we punish, since people can be wrongfully punished by criminalisation errors as well as by conviction errors.

Can I be a luck egalitarian and a Rawlsian?

Luck egalitarianism and Rawlsianism have been presented as competing answers to the same question: the question of distributive justice. In this paper, I show how they are in fact not different theories of the same thing, but rather different theories of different things - different answers to different questions. I trace the history of luck egalitarian thinking and try to show why Rawlsianism and luck egalitarianism were taken to be the same kind of project. I then examine different ways that one could consistently endorse (some version of) luck egalitarianism and (some version of/elements of) Rawls' theory.

Choices, chance and change: luck egalitarianism over time

The family of theories dubbed ‘luck egalitarianism’ represent an attempt to infuse egalitarian thinking with a concern for personal responsibility, arguing that inequalities are just when they result from, or the extent to which they result from, choice, but are unjust when they result from, or the extent to which they result from, luck. In this essay I argue that luck egalitarians should sometimes seek to limit inequalities, even when they have a fully choice-based pedigree (i.e., result only from the choices of agents). I grant that the broad approach is correct but argue that the temporal standpoint from which we judge whether the person can be held responsible, or the extent to which they can be held responsible, should be radically altered. Instead of asking, as Standard (or Static) Luck Egalitarianism seems to, whether or not, or to what extent, a person was responsible for the choice at the time of choosing, and asking the question of responsibility only once, we should ask whether, or to what extent, they are responsible for the choice at the point at which we are seeking to discover whether, or to what extent, the inequality is just, and so the question of responsibility is not settled but constantly under review. Such an approach will differ from Standard Luck Egalitarianism only if responsibility for a choice is not set in stone – if responsibility can weaken then we should not see the boundary between luck and responsibility within a particular action as static. Drawing on Derek Parfit’s illuminating discussions of personal identity, and contemporary literature on moral responsibility, I suggest there are good reasons to think that responsibility can weaken – that we are not necessarily fully responsible for a choice for ever, even if we were fully responsible at the time of choosing. I call the variant of luck egalitarianism that recognises this shift in temporal standpoint and that responsibility can weaken Dynamic Luck Egalitarianism (DLE). In conclusion I offer a preliminary discussion of what kind of policies DLE would support.

On fairness and claims

Perhaps the best known theory of fairness is John Broome’s: that fairness is the proportional satisfaction of claims. In this paper, I question whether claims are the appropriate focus for a theory of fairness, at least as Broome understands them in his current theory. If fairness is the proportionate satisfaction of claims, I argue, then the following would be true: fairness could not help determine the correct distribution of claims; fairness could not be used to evaluate the distribution of claims; fairness could not guide us in distributing claims (or unowed goods); we could not have a claim to be treated fairly; and we would not be wronged when treated unfairly. These entailments mean that it is questionable that fairness is concerned with claims in the way Broome suggests. At the very least, the relationship between fairness and claims appears to be more complex than the picture painted by Broome.