Note: there is a separate EBPM podcast series and page EBPM | Paul Cairney: Politics & Public Policy (wordpress.com)
Note: this is a longer lecture, and one of many (see also ANZSOG | Paul Cairney: Politics & Public Policy (wordpress.com) and The Politics of Evidence-Based Policymaking: ANZSOG talks)
From Policy Concepts in 1000 Words: ‘Evidence Based Policymaking’:
The term ‘Evidence Based Policymaking’ is in common currency in media and social media. It often represents an ideal which governments fail to reach. A common allegation is that policymakers ignore and/ or do not understand or act on the correct evidence. However,  if you look at policy studies, you tend to find highly critical discussions of the concept, and the suggestion that people are naïve if they think that EBPM is even a possibility. Some of this is simply to do with a lack of clarity about what EBPM means. Some of it is about the claim in policy studies that people don’t understand the policy process when they make EBPM claims. We can break this down into 2 common arguments in policy studies:
1. EBPM is an ideal-type, only useful to describe what does not and cannot happen
EBPM should be treated in the same way as the ideal-type ‘comprehensively rational policymaker’.  By identifying the limits to comprehensive rationality, we explore the implications of ‘bounded rationality’. For example, by stating that policymakers do not have the ability to gather and analyse all information, we identify the heuristics and short cuts they use to gather what they can. This may reveal their biases towards certain sources of information – which may be more important than the nature of the evidence itself. By stating that they can only pay attention to a tiny fraction of the issues for which they are responsible, we identify which issues they put to the top of the agenda and which they ignore. Again, there is a lot more to this process than the nature of the evidence – it is about how problems are ‘framed’ by their advocates and how they are understood by the policymakers held responsible for solving them.
2. Scientists use evidence to highlight policy problems, but not to promote policy change 
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