What Properties of Norms can we Implement in Robots?

Norms are indispensable for human communities, and so they will be for robot-human communities. We analyze some of the requirements for a robot to represent norms and conform its actions to them. These requirements include both cognitive and social properties that human norms instantiate. We examine which of these properties can be implemented in a robot's architecture and review some previous computational approaches. We then introduce an approach using behavior trees, argue for its promise to implement properties of norms, and discuss unsolved challenges.