Over the past two decades, Urban Living Labs (ULL) emerged as a special derivate of policy labs. These are a relatively young phenomenon that is characterized by a strong orientation towards design thinking and the generation of evidence for policy-making processes. Research on this topic is rising, yet there is need for more empirical evidence that informs explanations of how policy labs in general and ULLs in particular are successfully depoliticizing and objectifying debates in the science-policy nexus, for example in wicked areas such as sustainable transport policy. Drawing on two ULLs in local policy communities in Germany, the central research question asked is how different types of policy labs with diverging salience levels of science and politics effectively contribute to an evidence-based debate on policy solutions. Answering this question for a topic characterized by high levels of complexity, emotions, and uncertainty potentially provides generalizable insights for different types of policy labs:The results indicate that policy labs may effectively move the debate from political motivation to scientific knowledge, but only if science is given a real role within the policy lab.

How do social identities contribute to the formation of coalitions in a policy subsystem? Social identities help to understand the bundling of resources and common strategies for action. Thus, we argue that identification with a group and across groups discursively results in the formulation of shared and competing storylines. As coalitions are characterized by some kind of sameness of their actors which results in shared storylines, we thereby postulate that the link between storylines and social identities provides added value to the explanation of coalition formation. We test whether shared storylines can be traced back to social identities in the different discursive periods of traffic development on a local level in Germany. A media analysis of 110 articles and 14 interviews shows that the assignment of certain group characteristics is discursively confirmed, renegotiated, or rejected. Social identities, therefore, matter for coalition formation.

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