Focus on evidence-based policymaking is greater than ever, and public spending on evaluations is rising. A primary merit of these expenditures is that politicians actually use new knowledge instrumentally--to influence and inform decision making. Nevertheless, we know surprisingly little about whether and how research-based knowledge is utilised. This paper presents a new way of documenting Degrees of Knowledge Utilisation: The DoKU-scale. The scale is tested empirically in a five-year meta-evaluation covering 54 evaluations and 334 legal sources. Through robust method triangulation, the DoKU-scale enables comparison of knowledge utilisation across large numbers of knowledge sources and over time.