This high-stakes day featured intensive cross-examination and redirect of LAPD criminalist Gregory Matheson, with the defense systematically building allegations that O.J. Simpson's reference blood sample was used to plant evidence at the crime scene. Blasier established that approximately 1.5 milliliters of Simpson's blood are unaccounted for and that the sample was improperly stored in a trash bag overnight. A pivotal moment came when type B blood found under Nicole Brown Simpson's fingernails—which does not match Simpson's type A—was presented as evidence of an unidentified third party. The prosecution countered with detailed testimony on lab security protocols, card access logs, and scientific explanations for blood degradation patterns.

• Defense establishes approximately 1.5 milliliters of O.J. Simpson's reference blood sample are unaccounted for
• Reference blood sample revealed to have been stored improperly in a trash bag overnight
• Type B blood under Nicole Brown Simpson's fingernails does not match O.J. Simpson's type A blood, establishing alternate perpetrator theory
• Prosecution presents lab card access logs and security testimony showing no unauthorized access to evidence processing room
• Heated scientific debate over EAP blood type degradation patterns; Matheson concedes observed banding pattern does not match published literature
• Defense moves to admit knife exhibit 118 found post-metal detector sweep with type B blood; prosecution calls it 'ludicrous red herring'