This short series titled Evidence as Politics in Policy explores a simple but often overlooked point: evidence does matter in policymaking, but never on neutral ground. In all political systems, evidence is used strategically, selectively ignored, unevenly protected, and shaped by democratic and non-democratic pressures, institutional design, and political incentives. Across these articles, I argue that the challenge is not simply to produce more evidence or communicate it better, but to understand the political, economic and social conditions under which evidence is used, contested, or sidelined — and what that means for anyone interested in evidence-informed policy.
The reflections in these articles have been drawn from a series of interviews with political scientists in Latin America, Africa and Asia as part of our ongoing effort to better understand the political economy of evidence use.
Read until the end for summaries of the interviews.
One of the most persistent assumptions in discussions about and projects to promote evidence-informed policymaking is that evidence enters politics as a neutral input: a body of facts waiting to be considered by rational decision-makers.
That is not how politics works. +
In all political ecosystems, especially those marked by ideological polarisation, electoral competition, imperfect decentralisation, and intense public pressure, evidence is never neutral. It is actively selected, framed, timed, deployed, and ignored in ways that are deeply political.
Evidence can still matter a great deal, of course; but it does not matter in the way many technocratic accounts of policymaking suggest.
Evidence as a political instrument
In complex political environments (don’t they all feel complex these days?) evidence often functions less like a shared foundation for collective problem-solving and more like an instrument in an ongoing political struggle.
People forget, but it is worth remembering that much of our current work on “evidence-based policy” has its origins in the “new style” of politics promoted by political giants like Tony Blair and Bill Clinton.
So, rather than being neutral, evidence is sometimes used as a:
- Political weapon: Reformers use evidence to challenge entrenched practices, defend new policy directions, or expose failures in existing frameworks or systems. Their opponents, in turn, use alternative evidence, selective evidence, or competing interpretations of shared facts to resist change and justify the status quo. In highly politicised sectors, evidence becomes part of the contest rather than a way out of it.
- Political shield: Evidence is a cop out. Political leaders may invoke studies or expert reviews not because they want to be guided by them, but because they want cover or to avoid the responsibility of making a decision. Outsourcing a contentious decision to researchers or technical experts can help redirect criticism, diffuse political responsibility, or create the appearance of due process. Evidence, in this sense, does not remove politics from decision-making, but it helps manage the political risks around it.
- Badge of political legitimacy: In closed settings, evidence may help individuals or groups to claim a right to participate in political debates. What the evidence says matters less than where the evidence comes from or who produced it.
Evidence is often reactive, not strategic
Another common assumption is that governments seek evidence to plan better. We have all seen those policy cycle diagrams: identify a problem, do research to find a solution, implement the solution, etc.
This is true.
But something else is true as well. In practice, evidence is often sought in a much more reactive way.
Governments turn to evidence when a crisis erupts, when a programme fails, when media scrutiny intensifies, when the opposition raises uncomfortable questions, or when a powerful political actor demands justification for a decision. Evidence is often brought in after the fact: to explain, defend, repair, or contain.
In a study on DFID’s use of evidence back in 2010, Harry Jones and I found that, more often than not, bureaucrats used evidence to make sense of political decisions made by ministers.
If you have ever seen an episode of The Thick of It, then you know what I mean.
This is policy-informed evidence, and there is nothing necessarily wrong with it! It just means that evidence is not always shaping political choices but is instead used when responding to the consequences of those choices.
External pressures matter, too. In some contexts, governments may adopt evidence to satisfy donor requirements, comply with international agreements, or maintain credibility regarding trade, corruption, or democratic or competitiveness indices. In these cases, the motivation is not always an internal commitment to informed policymaking but more likely about reputation, access to finance, or diplomatic standing.
Again, evidence matters. But it matters in a setting where incentives are not primarily epistemic but political.
Not all parts of the State are the same
Another misplaced assumption is that the political character of evidence use plays out evenly across government.
In practice, some parts of the State rely on evidence more consistently than others. Ministries of Finance and Economy, Trade, or agencies subject to strong international scrutiny often have less room to improvise.
In such sectors, evidence may be used more routinely because governments cannot afford to gamble with core macroeconomic stability, fiscal credibility, or international commitments. These are also often more developed fields with a greater density of information and expertise, more frequent and robust feedback loops, and opportunities for public scrutiny and course correction.
By contrast, other ministries operate in much more openly political and ideological terrain. Education is a good example. It is close to everyday life, highly visible, emotionally charged, and full of actors with strong opinions and organised interests. In such sectors, evidence may still circulate widely, but it competes directly with public sentiment, political branding, union pressure, bureaucratic routine, and electoral calculation.
That distinction reminds us that the problem is not simply that some governments value evidence and others do not. Within the same government, some policy domains may be highly evidence-driven while others remain dominated by political symbolism, short-termism, or constant policy reversal.
I explored this relationship in an application of the density model:
| High density – Low political interest
Decisions are likely to be informed by research-based arguments, and this will be chosen and used using technical or academic criteria |
High density – High political interest
Decisions are likely to be informed by research-informed arguments, but this will be chosen and used using political criteria |
| Low density – Low political interest
Decisions are likely to be made by individuals or small and closed policy or interest groups and these are likely to be informed by personal values or interests or by the little research that is available |
Low density – High political interest
Decisions are likely to be informed by political considerations and based on electoral demands and the public’s values or interests: in other words: votes count |
The problem with the technocratic model
I have long argued that these assumptions about evidence use lead to the wrong diagnosis – which leads to the wrong treatment!
If we imagine evidence as something that should naturally be taken up by policymakers once it is made available, then any failure to use it tends to be interpreted as a failure of capacity, communication, or more; maybe we just need more and better (and more expensive) evidence.
It is not surprising that billions (this is not an exaggeration) have been spent on “gold standard” evaluations – and now evidence synthesis- with no end in sight. (And with little evidence that they have had any impact on policy.)
All of that may help, but will never be enough if evidence enters a context in which it is being used strategically, filtered through political incentives, or valued mainly when it helps manage conflict or risk, or deliver private objectives.
In such settings, the question is not simply whether evidence exists and is being used but by whom, for what purpose, at what moment, under what pressures, and with what consequences?
Those questions shift our attention from the supply of evidence to the politics of its use.
A more realistic starting point
Those of us who care about evidence-informed policymaking need a more realistic starting point for both research and action.
This begins by recognising that evidence (and calls for its use) does not sit outside politics waiting to improve it. It is part of politics; it affects politics and is affected by it.
Evidence can support reform, but it can also entrench positions. It can open debate, but it can also be used to close it down. It can help governments learn, but it can also help them protect themselves.
Evidence – even the best and most accurate evidence – is not good or useful on its own.
Or to put it another way: evidence, on its own, does not speak truth to power. People speak.
This new starting point forces us to move beyond the comforting fiction that more and better information naturally leads to better policy. It encourages us to look instead at the people, institutions, incentives, relationships, and power structures that shape whether evidence is taken seriously, selectively mobilised, or simply ignored.
Therefore, our approach to the use of evidence ought to prioritise the perspective of decision-makers rather than researchers.