Feature

Risky Business

How should governments interpret scientific assessments of risk?

Donald McGregor and Paul Moran

The role of the Office of the Chief Scientist is to ensure that the development of public policy, across the range of government, is adequately and properly informed by scientific and technological information, analysis and advice.

One of the consequences of the New Zealand science reforms over the past decade was that the scientific and technical expertise that previously resided within government, in DSIR and MAFTech, is now outside of government in Crown Research Institutes which are owned by the government, but not part of it.

CRIs and universities are focused on advancing science and developing technology. There is a gap between government and the national reservoir of scientific and technical expertise. The role of the Chief Scientist is to help bridge this gap and enable the government to tap the appropriate scientific expertise as and when required.

A topical example is BSE -- bovine spongiform encephalopathy. Within a week of the announcement in Britain of a possible link between BSE and CJD, the government set up an Expert Science Panel to provide independent analysis and assessment of scientific information as it came to hand.

BSE is a very good example of how governments are faced with making decisions on the basis of incomplete and imperfect information. It is also provides a good illustration of how the business of government is as much about risk management, risk communication and addressing perceptions of risk as it is about providing estimates of the probability of particular risks -- risk analysis. For politicians and officials within government risk management, risk communication, and addressing public perceptions of risk are as important as analyses of the probabilities of particular risks.

Risk assessment is much more than probability analysis. Assessment implies judgement. People and politicians make judgements, not just on the basis of statistical information, but also according to their perceptions of risk and the values to which they subscribe. If statisticians are to make useful contributions to decision-making where there is uncertainty about the facts, they must communicate this uncertainty in a language that politicians and the public understand.

Consistency and Transparency

There are 38 government departments and agencies offering advice on different issues: the Ministry of Agriculture provides advice on plant and animal health, the Ministry of Forestry on forests, the Ministry of Health on human health, and so on. The Cabinet looks for consistency in the advice coming from departments. But expertise in risk assessment is not evenly distributed throughout government departments. Officials in government need to do more to ensure that there is a better appreciation of risk assessment across government. We also need to improve understanding of comparative risks, for example to put risks associated with microwave transmitters in school grounds in context with other risks such as those associated with children crossing the road on their way home from school.

Decisions based on risk assessment must be transparent. The information and analysis on which decisions are based must be open to public scrutiny. This is vitally important for maintaining public confidence in the government's decisions. In New Zealand, we are well served by the Official Information Act, which ensures that the information on which almost all decisions of government are based is madepublicly available. This places a valuable discipline on those involved in decision-making -- they know that they must be able to publicly justify and defend their decisions. Our Office places considerable emphasis on external peer review of the scientific and technical advice it provides to government.

The Economic Connection

One of the dominant trends of the second half of the 20th century has been the globalisation of trade and industry. If we are to make a living we must compete in a global market and live in a global economy. New Zealand has been a strong supporter of the removal of economic barriers to trade. We need markets for our products. But open access to the world markets is a reciprocal agreement. As our economy becomes more open, grows and diversifies, we are exposed to a new and growing range of environmental risks -- ballast water from Korea and China, unwanted pests as hitchhikers on imports of Japanese used cars and used tyres, tourists with fruit carrying insect pests from Australia, Asia or the United States.

The best-practice approach to managing risks to the economy and the environment is now recognised to be through risk assessment. Among the questions that need to be asked are:

• how should acceptable risk' be determined?
• what is the potential for a more quantifiable approach to risk assessment?
• how should international obligations affect quarantine risk assessment?

In the past, our policies and those of our trading partners have been motivated to achieve zero-risk -- "when in doubt, keep it out", or "exports okay, imports no way". This policy has been less than effective. New Zealand itself has endured many examples of trade barriers in the export of its agricultural products.

If New Zealand is to competently manage the international trade risks to its human, animal, plant and environmental health in the World Trade Organisation environment, we shall increasingly rely on competence in risk management and in the underpinning science.

Risk and uncertainty relating to our environment -- the physical, social and cultural environment, as defined in the Resource Management Act -- demands careful attention to the full range of scientific knowledge available to us, and a determination to extend the knowledge boundaries further still. Environmental issues inevitably involve uncertainty, and science-based assessments must not be allowed to hide or ignore these uncertainties. Policy decisions based on risks to the environment must be influenced by the weight of evidence.

A key feature of risk assessment is that it has the potential to highlight where more knowledge is needed to improve the basis of decisions and to help to establish a common ground between groups with disparate views. But risk assessment by itself is not necessarily a path to consensus.

As uncertainty surrounding risks increase, there is also likely to be an increasing disparity of views between different interest groups and government departments. A good example is the accidental introduction of pests through the importation of second-hand cars and tyres from Asia. Those whose primary responsibility focuses on trade and the economy would point out that any trade barriers imposed by New Zealand would represent a market distortion, and would also result in a weaker trade-negotiating stance internationally. Others, with a primary mandate to protect the environment, would point to the risks and consequences of introduction of pests such as Asian Gypsy Moth and Asian Tiger Mosquito. It is critically important that the risk assessments are underpinned by the best possible science.

When dealing with risk in the face of uncertainty, scientists have no privileged status -- there is no metric of risk aversion. The level of risk that we, as a society, are prepared to accept in the face of scientific evidence will depend on complex social, cultural, economic and environmental factors. The elected representatives of society are best placed to judge these factors, for which they have the ultimate responsibility.

The idea that "the nexus between research and policy is like the nexus between sin and confession: if you have not partaken in the first, you will not have much of interest to say in the second" may well be valid. However, the policy views of individual scientists are of no more importance than anyone else's..

Legislative Response

In an attempt to manage the risks posed to society by hazardous substances and new organisms, Parliament has passed legislation that will establish the Environmental Risk Management Authority (ERMA) to oversee and control them. ERMA will play a crucial role in determining how risk-averse we are as a society to hazardous substances and new organisms. Risk assessment will be a key feature of ERMA's activity.

Unless the science-based advice provided to governments is open to scrutiny and carefully explained, we run the risk of disenfranchising our society and creating an intellectual backlash that drives people to cocoon themselves in intransigent positions. This is at the core of the growing problem of society's distrust of science and technology. Decision-makers must avoid the human tendency to reduce the set of possible consequences or outcomes in order to make a decision manageable. We must ensure that all consequences of various options and risks associated with them are considered.

In summary, risk assessment needs to be an objective and transparent process, underpinned by good science and taking into account the full range of consequences and their associated uncertainties. Scientists must endeavour in the future to address the knowledge gaps identified during risk analysis, and to communicate to decision-makers and the public what risk assessments can and cannot tell us. We need to harness together our scientific techniques and our communication skills to enable society as a whole to make consistent and intelligent decisions when dealing with risk.

Donald McGregor is the Chief Scientist at the Ministry of Research, Science and Technology.
Paul Moran is a Science Advisor at the Ministry of Research, Science and Technology.