  Context: Using student subjects in empirical studies has been discussed
extensively from a methodological perspective in Software Engineering (SE), but
there is a lack of similar discussion surrounding ethical aspects of doing so.
As students are in a subordinate relationship to their instructors, such a
discussion is needed. Objective: We aim to increase the understanding of
practices and perceptions SE researchers have of ethical issues with student
participation in empirical studies. Method: We conducted a systematic mapping
study of 372 empirical SE studies involving students, following up with a
survey answered by 100 SE researchers regarding their current practices and
opinions regarding student participation. Results: The mapping study shows that
the majority of studies does not report conditions regarding recruitment,
voluntariness, compensation, and ethics approval. In contrast, the majority of
survey participants supports reporting these conditions. The survey further
reveals that less than half of the participants require ethics approval.
Additionally, the majority of participants recruit their own students on a
voluntary basis, and use informed consent with withdrawal options. There is
disagreement among the participants whether course instructors should be
involved in research studies and if should know who participates in a study.
Conclusions: It is a positive sign that mandatory participation is rare, and
that informed consent and withdrawal options are standard. However, we see
immediate need for action, as study conditions are under-reported, and as
opinions on ethical practices differ widely. In particular, there is little
regard in SE on the power relationship between instructors and students.
