Day 79 featured intensive cross-examination and redirect of DOJ DNA analyst Gary Sims on the core DNA evidence from the Bronco and Bundy locations. Barry Scheck systematically attacked the DNA evidence, establishing that Bronco samples showed dramatic increases in DNA content over time (suggesting planting), that the socks contained enormous DNA quantities, and that the DQ-Alpha typing had procedural irregularities that could indicate cross-contamination. Rockne Harmon conducted extended redirect examination to defend the evidence by walking through complete datasets and explaining the lab's controls and methodology. The day featured a technical but high-stakes battle over the reliability and integrity of the prosecution's DNA evidence.

• Scheck establishes that Bronco samples collected Sept 1 contained dramatically more DNA than same areas collected June 14 (40.5 ng vs 2.6 ng), implying planting or contamination
• Scheck attacks DQ-Alpha typing of stain 31 for having a questionable 1.3 allele dot that per protocol should have triggered reanalysis
• Using a 37-combination genotype chart, Scheck demonstrates only 2 of 37 possible combinations in Bronco stain 303 include both victims' DNA together
• Scheck shows that 27-36% of the general population cannot be excluded as source of key allele on steering wheel stain
• Harmon rehabilitates evidence through redirect by walking through complete DQ-Alpha and D1S80 datasets and explaining substrate and negative controls
• Rehybridization of Bundy item 52 confirmed Sims' original 1.1, 1.2 call, according to prosecution testimony
• Sidebar dispute arises over whether redirect can include rear gate stain evidence using EAP/PGM markers; Ito allows limited redirect but signals no broader retrial