The trial day was dominated by extensive testimony from houseguest Kato Kaelin, who provided crucial prosecution evidence about the evening of June 12, 1994. Kaelin recounted three loud thumps on his bedroom wall around 10:40 PM on the south pathway, OJ Simpson's insistence on retrieving a mysterious dark knapsack before departing for the airport, and his observations that Simpson showed no visible injuries. The defense cross-examination focused on establishing Kaelin as a potentially biased witness through multiple pre-trial meetings with defense counsel and his increased acting work since the murders.

• Kato Kaelin testified about three loud thumps on his bedroom wall at approximately 10:40-10:45 PM on June 12, forceful enough to shift a framed picture
• Kaelin described OJ Simpson pointedly insisting on retrieving a mysterious dark knapsack from the driveway before departing for the airport
• Prosecution established through Kaelin's testimony that Simpson showed no visible injuries or bleeding on his hands throughout the evening
• Defense challenged Kaelin's credibility by establishing he had multiple pre-trial meetings with Shapiro, Pavelic, and Hostetler without recordings or notes
• Defense questioned whether Kaelin's increased acting opportunities since the murders represented a financial incentive affecting his testimony
• Rockingham videotape from June 13 was admitted despite foundational objections about the tape's source