  Researchers urge technology practitioners such as data scientists to consider
the impacts and ethical implications of algorithmic decisions. However, unlike
programming, statistics, and data management, discussion of ethical
implications is rarely included in standard data science training. To begin to
address this gap, we designed and tested a toolbox called the data ethics
emergency drill (DEED) to help data science teams discuss and reflect on the
ethical implications of their work. The DEED is a roleplay of a fictional
ethical emergency scenario that is contextually situated in the team's specific
workplace and applications. This paper outlines the DEED toolbox and describes
three studies carried out with two different data science teams that
iteratively shaped its design. Our findings show that practitioners can apply
lessons learnt from the roleplay to real-life situations, and how the DEED
opened up conversations around ethics and values.
