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Evidence-based policy as a political ideal

Authors: Kat Smith and Paul Cairney

This post was originally published by the Evidence & Policy blog on 11 May 2020.

We have re-issued the article that has already been published by the Evidence & Policy blog. We would like to express gratitude to the kind offer of the editorial board of the Evidence & Policy blog.

(Image credit: Evidence & Policy blog Kat Smith and Paul Cairney)

This new blog helps make the insights within Evidence & Policy accessible to all. In this opening post, the current Editors reflect on what they feel are some of the key insights about the interplay between evidence and policy:

1. Evidence does not tell us what to do.

It helps reduce uncertainty, but does not tell us how we should interpret problems or what to do about them.

2. There is no such thing as ‘the evidence’.

Instead, there is a large number of researchers with different backgrounds, making different assumptions, asking different questions, using different methods, and addressing different problems. Synthesising their research can be useful for policymakers, but risks providing advice from a too-narrow perspective. Similarly, focusing on a particular set of experts may exclude important insights from other disciplines.

3. Policy-relevant evidence is contestable and open to interpretation.

Researchers interpret data differently and debate the scientific implications which can lead to scientific controversy. Making a policy recommendation involves a further step in contestation and interpretation, which can pose dilemmas for researchers.

4. Many people and organisations are involved in translating evidence for policy.

They each provide a selective focus on some evidence at the expense of others, and add their own take on the implications. As interpretations of evidence are shared, ideas may change.

5. Networks and institutions act as evidence filters.

Networks are the relationships between policymakers and influencers. Institutions represent the formal and informal rules guiding practices. Both help explain how evidence is used in policy: relationships help facilitate trust in the messenger, while the rules help policymakers decide whose evidence is policy-relevant. This may involve ‘filtering out’ ideas that don’t fit with existing policy thinking.

6. It can be strategically useful to present decisions as ‘evidence-based’, but policy is necessarily political.

Many scientists promote the idea that policy should be ‘evidence-based’, and politicians often agree. Yet, it is also easy to show that governments rarely conduct evidence-based policymaking. Rather, policymaking is necessarily guided by values, beliefs and previous experience, alongside potentially relevant evidence. Markers of scientific credibility have symbolic value in policy. Downplaying the political use of evidence is a political act.

7. Policymaker attention to research evidence can be maximal or minimal.

Researchers can experience long periods of feeling ignored, followed by a sudden lurch of attention to everything they do. Or, their ability to influence policy with evidence resembles a ‘window of opportunity’, in which attention to a problem rises, there is only time to consider already-feasible solutions, and policymakers have a fleeting opportunity to act. Such ‘windows’ often prompt ‘scientific showdowns’, in which many actors promote their preferred solution, drawing selectively on evidence to try to enhance the credibility of their solution.

8. Numbers and projections about the future are seductive but potentially flawed.

The visual representation of numbers can represent an efficient and reassuring way to present evidence (so ‘killer charts’ can be particularly attractive). Models and projections are certainly helpful during crises, with projections providing the data ‘gold dust’ that policymakers seek. Yet, the oft quoted claim that ‘all models are wrong’ has merit and focusing overly on modelling can be risky. This is especially so if model data/assumptions are flawed or if policymakers’ attention is pulled away from other kinds of useful evidence.

9. Refining policy-relevant evidence is frustrating but necessary.

Scientists seek to improve their predictions and revise their conclusions as they process new information. This process can be frustrating for the policymakers trying to project certainty, and confusing to media and public audiences. Yet, making choices based on outdated information or advice is worse.

10. The ‘good governance of evidence’ requires transparency.

It is tempting for policymakers to retreat behind closed doors. Secrecy can help foster the kinds of open debate that are necessary in science and politics but can also fuel media criticism and public concern. The ‘good governance of evidence’ requires a willingness to be open about uncertainty and to learn from mistakes.

Kat and Paul are the current Co-Editors in Chief of Evidence & Policy. Kat Smith is a Professor of Public Health Policy at the University of Strathclyde and Paul is a Professor of Politics and Public Policy at the University of Stirling.

If you enjoyed this blog post, you may also be interested to read:


This post was originally published by Transforming Society on 20 May 2020.


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