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Transcript Document 260425

The Precautionary Principle and
Genetics
Michael Parker
What is the precautionary
Principle?
• Many definitions in the literature- virtually
every paper presents a different version
• A generic ‘negative’ version might be
something like the following:
• Where a course of action presents a ‘possible’,
‘credible’, ‘plausible’, ‘likely’ or ‘foreseeable’
chance of a ‘substantial’, serious’ ‘harm’, ‘threat’ or
‘damage’, the action should be avoided, even
where these is no conclusive evidence that the
harm or damage would have resulted from the
action
• But there are many different versions
The application of the
precautionary principle (PP1)
• The principle has often been called upon in
situations concerning the introduction of a
new technology:
• New medical process e.g. gene therapy/PCR
• Use of a new product e.g. GMOs, pesticides, dyes
• Where there is a perception that these pose a
threat/danger to:
• the environment, human health, ecosystems etc.
• And a belief that these harms should be
avoided even where there is no conclusive
evidence that they will/are likely to occur
Some initial thoughts about PP
(1)
• Definitions of key terms:
• What is to count as a ‘harm’, ‘damage’, ‘threat’?
• What does it mean for a harm, damage or threat to
be ‘serious’, ‘significant’?
• What is a ‘high’, ‘plausible’, ‘credible’ risk?
• What is to qualify as ‘certainty’, ‘conclusive
evidence’, ‘justification’, ‘good reason’?
Some initial thoughts (2)
• How coherent are the moral principles upon
which the precautionary principle depends?
• On first sight it appears to be based on two
such principles:
• A strong form of ‘negative utilitarianism’ i.e. that
in all cases the avoidance of harms ought to be
the primary moral concern
• The belief that there is a moral distinction between
‘acts’ and ‘omissions’. E.g. That stealing £5 from
someone is worse (morally) than failing to give
someone £5 (implications for 3rd world)
• But, how coherent are these principles, either
individually or in combination?
The limitations of the PP
• In my talk today I shall argue that these two
sets of concerns must be taken seriously.
That is:
• Concerns about definitions
• Concerns about moral principles
• I shall conclude that, the PP must either be
rejected or modified by other moral principles
if it is to be coherent
• I shall argue that it may be possible to arrive
at a coherent conception of the PP but this is
only possible within a framework of other
obligations
Precaution in genetics
• Genetics is an ideal target for the application
of the precautionary principle:
• It involves the development and use of new
technology
• In many, most, cases the risks are uncertain i.e.
a positive test result often identifies a risk without
quantifying it e.g. SCD and ‘risk iceberg’
• In many cases, the potential harms are very
serious and significant e.g. ‘sudden death’
• Here are some examples in clinical genetics
Case One
On the basis of her age and other risk factors,
a woman who is 10 weeks pregnant is
informed by her doctor, following a question
from her, that she is at approximately 1:800
risk of having a child with Down Syndrome
She is very concerned about this and asks for
a prenatal test (CVS). She says that she will
terminate the pregnancy if affected
She is told that CVS brings with it a 1:50 risk
of miscarriage. She understands this but
insists that she wants to have the prenatal
test. Should it be provided?
Case Two
Susan and Tim are informed about the
diagnosis of a rare autosomal recessive
condition in their new born baby.
The condition is severe and there is a high
chance that the baby will die in the first year.
The genetic counsellor informs the couple
that they have a 1 in 4 chance of any future
baby being affected by the condition.
Tests on the blood samples reveal that Tim is
not the child’s biological father. Polly refuses
permission for the clinic to inform him.
Should Tim be informed?
Case Three
Rachel is an unaffected carrier of SED.
This is an x-linked condition which only affects boys.
At birth, they are of normal proportions but during
childhood their growth is retarded and their adult
height is usually around 1.5 metres.
They tend to get some back and joint pain,
osteoarthritis and restricted movement and in some
cases, early hip replacement and pain management,
is required. But, in most cases the care is ‘support’,
and advice to avoid certain occupations. Affected
boys have normal intelligence and life expectancy.
Rachel requests prenatal testing. Should this be
available?
Precaution and Genetics
• These cases show why genetics is an
obvious target for the precautionary principle
• I suggested earlier that PP is most commonly
used in relation to introduction of new
technology. Genetics is a good example (e.g.
gene therapy, new tests).
• In such cases, the precautionary principle is
usually taken to suggest that we should not
introduce a new technology, if it poses a
‘significant threat’, even if it cannot be
conclusively shown that the threat will
materialise
The ‘threat’ of inaction
• The origins of the PP in environmental ethics and
emphasis on avoidance of harms, explain the
emphasis on restraint in the use of technology
• In the medical arena however, it becomes more
obvious that failing to act can also present a serious
threat
• E.g. from failure to implement public health
measures. Or, consider again the cases I described.
• This suggests that being serious about the avoidance
of harms requires one to consider the consequences
of both action and of inaction
• This is a point made by many commentators on the
PP: Englehardt, Vineis, Vineis+Ghisleni,
Harris+Holm, Häyry and others
Precautionary principle
(version 2)
• This suggests the need for a revision of our
first version of the PP to something like this:
• Where there is a perceived serious threat we
should choose the action or the omission that
best minimises the likelihood of harm e.g.
introduce a public health measure or decide not to
use a potentially toxic pesticide
• This rewording makes it clear that to be
coherent, the PP must require an
assessment of the potential harms of all
available actions or omissions even where
the risk of such harms is unclear
The PP in practice
• But, this rewording doesn’t reflect the way the
PP is most often used in practice
• Despite the conclusion that PP should treat
both action and inaction with equal suspicion,
the PP as currently practised tends to place
greatest emphasis on the significance of
actions i.e. people use PP1
• Origins in concern about environmental
damage explain this, but this does not make it
coherent
• This implicit belief that harm caused by
inaction is less morally blameworthy than
action needs to be analysed
Three possible justifications for this
• The status quo is of intrinsic moral value
and should only be changed where there is
very good reason to do so
• But, change is inevitable
• Belief in the value of the ‘natural’ as good or as
stable is untenable
• Ecological arguments about the dangers of
rapid change- genetic stress
• True that rapid change can cause harms, but
sometime inaction can also lead to rapid change
• Or, that there is an intrinsic moral
distinction between acts and omission
What is wrong with Acts-Omissions?
• As negative utilitarians it is difficult to see why PP
advocates should care how a harm results, the
concern is to avoid it
• Some might be tempted to argue that even if harm is
the same, it is less bad if we didn’t actively cause it
• They have ceased to be utilitarians
• James Rachels’ thought experiment
• So, if advocates of PP are negative utilitarians they
should simply avoid harms, whether by action or
omission. They should be neutral about technology
(Englehardt)
• This is the only coherent form of negative
utilitarianism
But, should we be negative
utilitarians?
• Overriding principle of negative utilitarianism is the
avoidance of harm/misery
• Hence the appeal for advocates of environmental
caution
• But, the only certain way to avoid all harms would be
the painless extermination of all life (Glover)
• So, the avoidance of harms cannot be the only moral
concern when thinking about genetics or other new
technologies
• Must also be at least some role in the consideration
of decisions about technology for the production of
benefits
Precautionary principle
(version 3)
• Calls for another revision: PP3
• In addition to being concerned with the effects
of both acts and omissions, a coherent
version of the principle requires a
consideration of both harms and benefits
• To be ‘precautionary’ however the principle
would have to be such that, where there was
uncertainty, the avoidance of harm should
trump the promotion of benefits
• But, what are the implications of this third
version of PP when applied in the arena of
genetics and reproduction?
A Case
• A woman wishes to use sex selection to avoid
having a girl child. She considers girls to be
of intrinsically much less value than boys and
wants a son, who she will love.
• Knowing the woman well, the doctor
considers it very likely that if she has a girl
she will treat her extremely badly and neglect
her.
• Should the doctor provide sex selection
(sperm sorting) to avoid the possible harms to
a girl child conceived ‘naturally’?
• One could imagine a similar case involving
‘disability’
A need for other moral principles
• It ‘might’ be possible for the advocate of PP3 to argue
that overall, the consequences of providing sex
selection in such cases are worse than those of not
doing so and hence it would be wrong
• But even if so, this is not a good enough reason
• it suggests that discrimination is only contingently wrong
• This is not the case. Discrimination against women
and disabled people would be wrong even if it did
avoid more overall ‘harms’ or promote more overall
‘benefits’
• Implies a role for deontological concepts such as
justice, equality, fairness and autonomy (in addition to
thinking about harms and benefits)
Precautionary principle
(version 4)
• These arguments imply that moral decisionmaking, even if it takes the precautionary
principle seriously, also takes place against a
background of other, non-consequentialist,
principles, obligations and duties
• A coherent PP4 must consider: actions,
omissions, benefits, harms and do so in the
light of other obligations, duties etc.
• Confronting the moral challenges of decisionmaking in an empirically and morally complex
world requires moral ‘judgement’ concerning
competing moral demands
Justice and precaution
• This suggests that it might, theoretically at
least, be morally right under certain
circumstances to choose to risk a serious
harm where the avoidance of that harm would
conflict (badly) with another important moral
principle e.g. ‘justice’
• If, for example, failing to introduce a risky new
technology would be likely to lead to a vastly
more unjust world, it might under extreme
conditions be right to take the risk
• Use of GMOs in sub-saharan Africa might be
an example (possibly)
A final problem
• The complex moral challenges we face in an
increasingly uncertain world cannot be
addressed through the use of the PP alone
(PP1, PP2, PP3))
• Decision-making in the face of serious threats
and uncertain risks requires the use of moral
judgement in the light of competing moral
principles (PP4)
• But this raises the other concern I introduced
at the beginning of this talk: the ‘definition’ of
key terms
• Consider again, my first case:
Case One
On the basis of her age and other risk factors,
a woman who is 10 weeks pregnant is
informed by her doctor, following a question
from her, that she is at approximately 1:800
risk of having a child with Down Syndrome.
She is very concerned about this. She asks
for a prenatal test (CVS) and says that she
will terminate an affected foetus.
She is told that CVS brings with it a 1:50 risk
of miscarriage. She understands this but
insists that she wants to have the prenatal
test. Should it be provided?
Who is to decide?
• The use of key terms such as: serious harm,
significant threat, credible risk, convincing evidence
and so on, raises the question of ‘who should
decide what is to count as ‘serious’, ‘harmful’ and so
on? Are there any objective measures?
• Who should be involved in the moral judgement?
• This is not a question I can answer here, but it does
highlight the need for decision-making, even
precautionary decision-making, to be made in the
context of a genuinely democratic, transparent,
inclusive and reasonable process
• But, what role in decision-making about GMOs
should be given to sub-saharan countries, for
example? How do we consider future generations?
Conclusion
• We are confronted by an ever-increasing array of
difficult moral decisions with a technological aspect
• The potential harms and threats of (introducing or not
introducing) technology should play an important role
in decision-making
• But, this takes place against a background of other
important moral considerations e.g. justice
• And requires complex and sensitive moral judgment
• Concerns about democracy and about definitions
imply the need to also take seriously the importance
of the nature of the decision-making process
• Such decision-making should be inclusive, open and
fair