Answer for Petit

I realised that this would be unreadable as a comment, as it's so darned long! "Petit" asked:

I don't understand how rhetoric is an improvement over evidence based policy. As far as I know this was an attempt to combat rhetoric and policies which were implemented purely for political reasons.

Will have to read the papers but from my limited practical experience I can't see how using rhetoric (argumentation) is any different from old style policy making.

It is also already common to argue for the applicability of ones evidence to a policy.

Hi Petit (Is that Petit Careme? Hello there!),

Good questions. These tend to be the questions that arise in presentations and, to a lesser extent, from reviewers. Arguments in favour of "rhetoric based policy making" tend to exact one of two reactions - either "evidence is good, anything else is just plain wrong" or "what's the problem? Surely nobody believes evidence alone is sufficient to make good policy" I hope the following rather lengthy comment will address both those questions:

First and foremost, I want to make it clear that there is a huge distinction between healthy rhetoric (consisting mainly of argumentation and dialectic) and unhealthy, eristic rhetoric.

The healthy type of rhetoric is desirable because the problems of "evidence based policymaking" are threefold (at least!):

1. Evidence can only tell us which policies are possible, not which ones are desirable.[1]
   
   
2. Knowing what is "the best" policy is impossible - policy making problems are wicked problems by their very nature. If a problem is reducable to a computable decision it wouln't be a policy decision, it would be a technical decision.
   
   
3. Policy makers are of course human beings first and foremost - and to pretend they are not suceptible to the unhealthy rhetoric of cranks an pressure groups is naive, and yet EBPM expects policy makers to behave as automata.
   
   Only by making policymakers aware of the difference between healthy and unhealthy rhetoric can we inocculate policy makers against cranks.
   

Trevor Bench-Capon sums up the need for argumentation (healthy rhetoric) in all practical reasoning:

Argumentation is essential because no completely compelling answer can be given: whereas in matters of belief we should be constrained by what is actually the case, in matters of action no such constraints apply - we can choose what we will attempt to make the case

(Emphasis mine.)

Therefore there is no function from a given set of evidence to a single, provable or probable "best" policy answer. Good rhetoric must include arguing about the applicability of evidence to a policy choice, the laying out of warrantss. But it should go beyond that, and argue over the reasons why a particular policy is desirable. Determining the most desirable policy that "we will attempt to make the case" requires that values and frames of the stakeholders to the policy are taken into acounct. For example, in deciding on a policy to reduce teenage pregnancy:

• We might all accept the premise that reducing teenage pregnancy is a worthwhile goal
  
• We would, I hope, not be at odds over the mechanics of conception
  
• We may still vehemently disagree about the preferred “means of action” taken to prevent teenage pregnancy - eg: abstinence education vs universal acces to contraception
  
• We may both still be behaving reasonably, according to our value systems
  

Even the evidence that one policy reduces teenage prgnancy n% more effectively than the other may not be sufficient to mandate the choice of one policy over another, if other matters of importance ("personal autonomy", "child welfare") are not taken into account. But there is no non-arbitrary way to make all these factors commensurable.

If you choose but one reference, I suggest Majone's Evidence, Argument and Persuasion in the Policy Process. It's pretty widely available and very readable. It certainly makes the case more cogently than I have here.

[1] There is an excellent example of good evidence leading to a totally defective policy (in that it failed to identify the real needs of the policy beneficiaries). This is the case of the "foam hip protectors" (referred by the frustrated users and their carers as "padded knickers") prescribed to elderly residents of an old people's home. The original study is:
Parker, M. J., Gillespie, W. J., & Gillespie, L. D. (2006) "Effectiveness of hip protectors for preventing hip fractures in elderly people: systematic review", BMJ, vol. 332, no. 7541, pp. 571-574.

and Green's review of the detremental effect on the dignity and quality of life of the people made to wear these devices:

Green, J. (2000), "Epistemology, evidence and experience: evidence based health care in the work of Accident Alliances", Sociology of Health and Illness, vol. 22, no. 4, pp. 453-476.