Comparative Analysis of Witness Testimony: Samuel Zulu's Witness Forensic Psychology (WFP) and Hugo Münsterberg's On the Witness Stand

Abstract Witness testimony remains one of the most contested and fragile forms of evidence in judicial systems worldwide. Its decisive influence in courts has long been challenged by psychological research demonstrating the fallibility of human perception, memory, and recall. In 1908, Hugo Münsterberg published On the Witness Stand, a pioneering text that introduced experimental psychology into the courtroom (Münsterberg, 1908). His work exposed the vulnerabilities of witness accounts, highlighting phenomena such as perceptual illusions, memory distortions, and susceptibility to suggestion. Although groundbreaking, his insights were often dismissed by legal practitioners of his time (Loftus, 2005). More than a century later, Samuel Zulu advances this dialogue by originating Witness Forensic Psychology (WFP), a discipline that formalises witness analysis into a lexicon‑driven scientific framework (Zulu, 2026a). WFP introduces 164 original terms and protocols including the Safehouse Integrity Index, Accuracy Intelligence Quotient (AIQ), Digital Narrative Bias, and Testimony Integrity Quotient (TIQ) that transform witness testimony from subjective narrative into quantifiable data. Unlike Münsterberg’s experimental demonstrations, Zulu’s WFP provides structured methodologies designed for direct application by courts, investigators, law enforcers, and law students. This article undertakes a comparative analysis of Münsterberg’s foundational insights and Zulu’s contemporary framework. It argues that WFP extends and modernises witness psychology for the 21st century by addressing risks unique to the digital era, such as social media contamination and systemic identification errors, while also safeguarding testimony integrity through measurable indices. By contrasting early experimental approaches with structured lexicon methodologies, the study demonstrates how WFP builds upon Münsterberg’s legacy, offering justice systems a new gold standard for evaluating witness credibility, reducing wrongful convictions, and strengthening judicial fairness.