Greening governmentthe courts than in Europe have seen the extensive employment of CBA to
determine court settlements.
Tosummarise, the environmental case for all three techniques is twofold:
they offerarational means of building environmental considerations, par-
ticularly those characterised by scientific uncertainty, into formal decision-
making processes and, therefore, they should also encourage policymak-
ers to anticipate and address the environmental implications of their
actions more routinely. Yet the techniques generate widespread criticism,
particularly from environmentalists; indeed, many experts suggest that
these techniques mayharmenvironmental interests rather than advance
them. The debate about their strengths and weaknesses focuses on five key
themes.
First, each technique claims to be a rational tool of analysis, yet none is
an exact science. Risk assessment, for example, is usually empirically based
on either animal studies or epidemiology, but often neither is reliable or
accurate enough to support conclusive risk assessments (Wildavsky 1995 ;
Armour 1997 ). The scientific claims of risk assessment are based on a sup-
posedly rigorous methodology that, in practice, usually relies on ‘a multi-
tude of assumptions and subjective judgements as much as it depends upon
empirical observation or testing’ (Rosenbaum 1997 : 42). Consequently, many
risk estimates are very tentative, making them vulnerable to challenge from
further scientific research, which can have embarrassing and expensive con-
sequences for policymakers. Thus, in 1974, when studies revealed that diox-
ins contained in waste oil sprayed on roads in Times Beach, Missouri, might
be highly carcinogenic and have contributed to ill-health in children and
horses, government officials ordered all residents to evacuate the city at a
cost of $139 million. A few years later the senior official responsible testi-
fied that subsequent studies suggested that the evacuation, although based
on the best available scientific evidence, had been unnecessary (Rosenbaum
1997 : 43). When the science underpinning risk assessment is rapidly advanc-
ing into new territory, as is currently the case with GMOs, definitive risk
assessment is almost impossible. The bottom line for risk assessment, as the
respected Royal Commission on Environmental Pollution ( 1998 )inBritain
put it, is that ‘No satisfactory way has been devised of measuring risk to
thenatural environment, even in principle, let alone defining what scale of
risk should be regarded as tolerable’ (para. 9.49).
Similarly, a serious methodological problem with CBA is the difficulty of
putting a price on environmental harms, such as the loss of scarce habitats
or damage from acid rain. Techniques do exist that attempt to overcome
this problem, such as contingent valuation, which asks people how much
they would pay to protect a threatened habitat (Pearce et al. 1989 : 69–71).
There are also several techniques for calculating the value of human life.
However, they cannot disguise the imprecision and subjectivity that lie at
theheart of CBA (ironically, many policymakers like the way CBA produces
asingle, definitive figure for each proposal that allows them to announce a