Day 4 was largely consumed by contentious pre-trial matters, with opening statements postponed to the following day. The defense blindsided prosecutors with a supplemental witness list of 34 names and undisclosed materials submitted on the morning opening statements were supposed to begin. The court worked through numerous exhibit disputes, deferred a ruling on the defense's controversial motion for Simpson to physically demonstrate knee limitations, and addressed discovery quarrels over evidence handling and the defense's right to cross-examine Detective Fuhrman about alleged racial animosity. The jury was finally brought in late in the day for pre-instructions only.

• Defense submitted 34-name supplemental witness list with undisclosed materials on morning opening statements were scheduled, many witnesses unvetted
• Prosecution and defense clashed over Simpson's proposed physical demonstration of knee scars and limitations to jury
• Judge Ito sustained objections to pheno test photographs but overruled objections to crime scene evidence photos P-35 and P-44
• Prosecution objected to 20+ defense exhibit boards and visual aids, with judge sustaining objections to calendar and sock timeline
• Judge confirmed defense has constitutional right to cross-examine Detective Fuhrman on racial bias and animosity
• Judge Ito issued formal courtroom conduct order establishing ground rules for audience behavior and trial procedures
• DNA discovery dispute emerged regarding autorads and slot blots never provided to defense
• Jury brought in late in proceedings for pre-instructions; opening statements delayed to following morning