Distinguishing Facts and Values in Public Policy Debates

At The Incidental Economist, I write about how the role of scientific evidence in public policy making is often misunderstood and misrepresented. That essay in turn stems from a BMJ article (partly gated) co-authored with Dr. Peter Piot, the founding Director of the UN Office on AIDS, in which we discuss how science is essential to good policy making, but can’t make critical decisions about priorities and morals for us.

It is thus facile to say that public policy makers should just “do what the science says”. Science doesn’t tell us to do anything. As Mark Kleiman once quipped, if your data “suggest” things to do, you should seek psychiatric help. Science is there to give us information, and the rest of how we run society is down to voting, values and political debate, which is at it should be in a democracy.

UPDATE: For a great take on these issues in drug policy, see this post by Alejandro Hope.

Author: Keith Humphreys

Keith Humphreys is the Esther Ting Memorial Professor of Psychiatry at Stanford University and an Honorary Professor of Psychiatry at Kings College London. His research, teaching and writing have focused on addictive disorders, self-help organizations (e.g., breast cancer support groups, Alcoholics Anonymous), evaluation research methods, and public policy related to health care, mental illness, veterans, drugs, crime and correctional systems. Professor Humphreys' over 300 scholarly articles, monographs and books have been cited over thirteen thousand times by scientific colleagues. He is a regular contributor to Washington Post and has also written for the New York Times, Wall Street Journal, Washington Monthly, San Francisco Chronicle, The Guardian (UK), The Telegraph (UK), Times Higher Education (UK), Crossbow (UK) and other media outlets.

15 thoughts on “Distinguishing Facts and Values in Public Policy Debates”

  1. “There is something fascinating about science. One gets such wholesale returns of conjecture out of such a trifling investment of fact.”

    Mark Twain
    Life on the Mississippi

  2. When I read this I thought “No, sometimes the science really does tell you what’s best.” But then I realized that I was limiting the universe of moral and political positions so that, say, the deliberate destruction of modern civilization or the reduction of wealth for all centiles combined with an increase in inequality were not things that anyone might possibly advocate.

  3. Sometimes the policy implications are so clear – whether to address climate change, smoking indoors with children present – that there’s not that much to talk about after science has had its say.

    1. There you go implying a desperately narrow range of ethical positions.

      Actually I agree with you — any time a set of policies imply a material gain for everyone, with only positional or internal values damaged, it’s hard to argue the other way. (Yet people do on a regular basis)

    2. Even where the policy goals are clear, there are often still problems revolving around resource allocation, harmful side effects, and so forth, which can make deciding on a “best” policy difficult.

    3. It seems there is not much to talk about if one works/lives in a setting in which everyone shares certain values, but once one ventures into the diverse country there are always values issues. This is something academics are often disoriented when they leave the ivory tower — it’s the shock of realizing that your values are subjective and not universal truths.
      For example, science might show that eliminating certain factories would reduce climate change but increase unemployment…and then we have to decide which we care about more. And on smoking indoors, some would argue that the cost of restrictions in terms of loss of freedom matter more than the health damage to children (I am not saying that is my own view, but that someone could see the evidence, believe it, and still not want a policy change)

      1. I was careful to say “whether” to address climate change – I agree that “how” has many policy implications that go beyond science. That said, I think whether to address climate change, and whether to smoke indoors with children present, involve such a broad set of universally-accepted human ethics that the science does provide the answer to these initial questions.

        How to address climate change, or how to get people to smoke less around children, those are subsequent and trickier questions.

        1. Brian Schmidt: universally-accepted human ethics

          Assuming for the sake of argument that such things exist, it would still be our ethics that were guiding our actions. That we agree doesn’t make it a technocratic decision to act on the science, it’s a moral/political decision.

          1. I should’ve said “nearly-universal” ethics, we’re too weird to get 100% consensus.

            Agreed that ethics/policy control the decision, but at a certain level the ethical question is so easy that the only thing you need to know is the science. That’s why I think the argument of folks like Roger Pielke Jr that climatologists shouldn’t discuss the need to address climate change is silly – the science slots into a broadly accepted moral/policy framework.

  4. The science never tells you what to do. Instead, it tells you what the opportunity set is. It does not tell you how to act within this set. But it often tells you what a reasonable decisionmaker shouldn’t do–act as if the opportunity set were really a pony.

  5. Science can also say, “Argument X for position Y is false.” That can be true if the factual premise for X is incorrect, or if the claim X does not in fact imply that action Y would have some claimed benefit. The line between description and evaluation is fuzzier than it sometimes seems, but those moves are closer to the “description” side of the room.

    1. Terrific post! I am amending my own to mention yours. What I said in the comment above to Brian Schmidt about academics applies also to many activists — they talk to each other a lot and do not realize that their values are in fact debatable, subjective views rather than facts.

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