Analyze

Peter D. Kramer is an American psychiatrist. Currently a faculty member of Brown Medical School, Dr. Kramer conducted most of the research included through patient interaction. As an opinion piece, the article does not carry a significant amount of hard, factual data. However, it should be noted that some factual information comes through published resources, such as current medical protocols held by the American Medical Association.

The article includes multiple in-person interviews, including with Canadian officials (such as the Nunavut Premier), a professor of psychiatry at the University of Saskatchewan, and several prominent figures in the Native community.

The article contains quotations attributed directly to the judge, so I would presume she was either present for the ruling or accessed the case brief. This would also be where Ms. Preston could obtain direct quotations from the plantiff's arguments. Additionally, the article includes statements from the EPA, public officials, and Senator Rodham Clinton; these would either be from official public releases or interviews by government personel. 

The NPR article appears to be a compilation of interviews (performed by the author and other media sources) with pertinent individuals (public health officials, economics experts) and research from agency reports (US Accountability Office, Institute for Justice and Democracy in Haiti).