Dr. Donald Dutton testified as a domestic violence expert for the prosecution, called to establish the psychological links between controlling behavior, estrangement, and the risk of spousal homicide — a framework central to the prosecution's argument that Simpson's history of abuse was a precursor to murder. His January 1995 testimony on this critical pre-trial admissibility motion drew a fierce cross-examination from F. Lee Bailey, who systematically challenged Dutton's methodology and ethics. Dutton resurfaced in the civil trial, where his expertise was again subject to contentious admissibility hearings alongside other expert witnesses.