Witness Reliability Triangulation

Witness reliability triangulation is the procedure by which a historian combines several testimonies about the same event to reach a justified conclusion about what happened. It rests on a simple but powerful logic: a single account, however vivid, may be mistaken or self-serving, but when independent sources that could not have colluded converge on the same point, the probability that they are all wrong in the same way becomes small. The method, descended from the classical source-critical tradition and sharpened by the social-scientific concept of triangulation associated with Donald Campbell and Norman Denzin, requires the historian to inventory the available testimonies, assess each one's reliability and bias through internal criticism, establish whether the sources are genuinely independent, and then treat their agreement as corroboration while explaining their disagreements. The same Bayesian intuition underlies the use of multiple, independent evidentiary streams in process-tracing case analysis. Triangulation is how disparate, fallible sources are turned into defensible historical knowledge.