A series of investigative reports being rolled out by the Wall Street Journal is putting a spotlight on the behind-the-scenes actions of Facebook. Ranging from rule exemptions for high-profile users to Instagram’s toll on teens’ mental health, the Journal‘s “Facebook Files” expose internal Facebook research that appears to show just how knowledgable the company was of the platform’s “ill-effects.” The Journal’s reports, three so far, are based on a review of internal Facebook documents, including research reports, online employee discussions and drafts of presentations to senior management.