Projects collecting data from vulnerable populations should consider risks posed to those populations.
While universities require a human subjects review, foundations and NGOs do not have the same infrastructure in place.
Even anonymized data can be re-identified when linked with other data sets. This is particularly dangerous where populations are not only marginalized but also criminalized.
For more on data practices for human rights practitioners, see DatNav, a guide to using digital data for human rights research, as well as this 2016 report on data ethics, and this handbook from the Responsible Data Forum.