The problem of online disinformation is only getting worse. Social media may well play a role in the the US 2020 presidential election and other major political events. But that doesn't even begin to describe what future propaganda will look like.
For most of human history, sudden and unexpected deaths of a suspicious nature, when they were investigated at all, were examined by lay persons without any formal training. People often got away with murder. Modern forensic investigation originates with Frances Glessner Lee - a pivotal figure in police science.