Final answer:
The term for using criminologist research to support the creation of policies like after-school programs to reduce juvenile crime is evidence-based policymaking.
Step-by-step explanation:
The connection between research showing that after-school programs can lead to reduced rates of juvenile crime and the implementation of said programs as social policy is referred to as evidence-based policymaking. This approach leverages empirical data and research findings to make informed decisions on creating and enacting policies that are more likely to be effective. In the context given, whereby a criminologist's research supports establishing an after-school program to reduce juvenile crime, evidence-based policymaking is at play.