Promoting equity and reducing inequalities: the role of evidence and science


The following article is authored by Paul Cairney.


Science and evidence are important to policy, and researchers can contribute to programmes that reduce social and economic inequalities. However, without understanding policy processes and how politicians process evidence, researchers will struggle to understand their – sometimes peripheral – role in the bigger picture. The following step-by-step list could help to better grasp and engage with these processes.  


The following steps help to understand and engage in democratic political systems: 


STEP 1: Embrace the value and necessity of politics.  


Politics should be at the heart of policymaking, helping to find non-violent ways to resolve diverse preferences held by people with different beliefs and interests through mechanisms such as electing people, parties or governments. Democratic mechanisms legitimise policy choices. Thus, trust in scientists – and the evidence they provide – is incomplete without trust in political systems. It is tempting to seek to replace choices by politicians with expert-driven technocracy, but the latter does not provide the same legitimacy.  


STEP 2: Accept that public policy is not, and never will be, evidence-based.  


Treat evidence-based policy as one of many contested phrases masquerading as self-evident aims. Others include follow the science or focus on what works. Each phrase suggests, misleadingly, that we can solve ideological debates with evidence.  


STEP 3: Seek practical lessons from scientific studies of policymaking. 


It is tempting to see scientists as the policy entrepreneurs that use their authority and powers of persuasion to prompt politicians to define and solve problems in better ways. However, policy theories highlight the wider contextual issues that limit politicians’ influence. Core insights include: 

  • Most policy changes are minor. Major change is unusual.  

  • Policymakers cannot pay attention to all issues and information. They use cognitive shortcuts – drawing on their trusted sources, beliefs, and emotions – to ignore most issues and evidence. 

  • Policymakers do not fully understand or control the processes for which they are responsible. Their environments contain policymakers and influencers spread across multiple policymaking venues, each with their own rules, ways of thinking and networks.  


STEP 4: Engage properly with political dilemmas.  


The close analysis of politics and policymaking allows us to identify key dilemmas that cannot be resolved via additional evidence. These dilemmas span diverse aspects of policymaking and implementation procedures. 


First, evidence cannot determine the role that the state plays (or should play) in addressing societal problems. Neoliberal approaches recommend low state intervention in favour of individual responsibility and market forces, while social justice approaches favour state intervention to address structural factors out of the control of individuals. Each approach produces major differences in the demand for evidence of a policy problem and assessment of what solutions work. 


Second, questions on the delegation of state responsibilities are not addressed via traditional evidence-gathering mechanisms. Political systems are multi-centric, with different levels and types of government taking responsibility for parts of a larger programme. Some seek a technocratic or optimal distribution of these responsibilities. However, the process to determine responsibility is highly contested, relating more to demands for territorial autonomy (or turf wars). Governments also delegate tasks to other organisations, producing a distribution of policymaking that defies simple coordination. This delegation of responsibilities requires researchers to understand where the action is and how to engage effectively in relevant systems.  


Third, there is no standard way to combine multiple sources of policy-relevant knowledge. Some scientists assert a hierarchy of knowledge: randomised control trials (RCTs) are gold, scientific expertise is bronze, and practitioner or service user experience would not make the podium. Other political actors prioritise the knowledge from people who deliver or receive services. Some seek compromise, to combine policy-relevant insights. However, their deliberations still involve choices, including whether policymaking should be centralised to roll out ‘evidence based’ solutions built on RCTs, or decentralised to allow local communities to draw on many knowledge sources in policy design.  


Finally, evidence cannot settle the debate between the maintenance of science’s image vs. the development of science’s influence over policy. In some political systems, scientists face dilemmas when their principles contradict the rules of government. Science emphasises transparency and independence to foster institutional trust and the credibility of evidence. Governments often require secrecy and informal rule-following to foster trust in advisers. Researchers must navigate this perspective mismatch when engaging with policymakers. 


Evidence-informed equity policies: two competing visions


The dynamics highlighted in these steps may vary across policy sectors. However, regardless of sector, a choice can be made between two methods of seeking evidence-informed policies to reduce inequalities. These methods are: 

  • A non-confrontational, technocratic project: offering radical change through non-radical action, mainstreaming equity initiatives into current arrangements and using a playbook to make continuous progress. This method is attractive because governments often project a sincere-looking rhetorical commitment to reducing inequalities. Yet, we find a tendency for radical aims to be co-opted to serve the practices that protect the status quo.  

  • A challenging political project: offering radical change through overtly political action and contestation, and translating rhetoric into substance by keeping the reduction of inequalities high on the agenda. In this case, there is no clear guide for action. Rather, participants accept that the impact of research-informed political action is uncertain and often unrewarding.  


Overall, the implications of policy engagement for researchers are profound. Too many evidence-to-policy initiatives are built on the misplaced idea that scientists can remain objective when engaging in politics. This leads to the equally implausible focus on detailed playbooks to replace political problems with technocratic solutions. Embracing the value of politics, and the inescapably political nature of research engagement, is the first step in considering a more realistic alternative. It requires engagement with the policy processes that exist, not the ones that scientists would rather see. 


Have you seen?
We politicised science and scientised politics – is that a problem?
Recalibrate - our policies were too heavy on efficiency, too light on equity
From ivory towers to glass houses, science is transforming




Cairney, P., 2016. The Politics of Evidence-based Policy Making. London: Palgrave Macmillan. 


Cairney, P. and Oliver, K., 2017. Evidence-based policymaking is not like evidence-based medicine, so how far should you go to bridge the divide between evidence and policy?. Health Research Policy and Systems 15(35). 


Cairney, P. et al., 2022. Lessons from policy theories for the pursuit of equity in health, education and gender policy. Bristol University Press. 


Oliver, K. et al., 2022. What works to promote research-policy engagement? Bristol University Press.  




Paul Cairney is a Professor of Politics and Public Policy at the University of Stirling in the United Kingdom.


The facts, ideas and opinions expressed in this piece are those of the authors; they are not necessarily those of UNESCO or any of its partners and stakeholders and do not commit nor imply any responsibility thereof. The designations employed and the presentation of material throughout this piece do not imply the expression of any opinion whatsoever on the part of UNESCO concerning the legal status of any country, territory, city or area or of its authorities, or concerning the delimitation of its frontiers or boundaries.