  Accountability aims to provide explanations for why unwanted situations
occurred, thus providing means to assign responsibility and liability. As such,
accountability has slightly different meanings across the sciences. In computer
science, our focus is on providing explanations for technical systems, in
particular if they interact with their physical environment using sensors and
actuators and may do serious harm. Accountability is relevant when considering
safety, security and privacy properties and we realize that all these
incarnations are facets of the same core idea. Hence, in this paper we motivate
and propose a model for accountability infrastructures that is expressive
enough to capture all of these domains. At its core, this model leverages
formal causality models from the literature in order to provide a solid
reasoning framework. We show how this model can be instantiated for several
real-world use cases.
