Douglas Deedrick, an FBI Special Agent specializing in hair and fiber analysis, delivered detailed forensic testimony for the prosecution over six days on the stand. Examined by Marcia Clark, he presented evidence linking trace fibers and hairs from the crime scene, the Bronco, and the victims' clothing, including carpet fibers from Simpson's vehicle matched to samples found at Bundy and hairs consistent with both Nicole Brown Simpson and Ron Goldman recovered from the gloves and knit cap. His appearance was contentious from the start — before he even testified, F. Lee Bailey accused the prosecution of deliberate discovery violations over late-disclosed fiber photographs and a hidden FBI report on Bronco carpet fiber rarity, which the judge ultimately barred from evidence. Bailey's cross-examination challenged the scientific validity of hair microscopy itself and exposed gaps in the investigation, while Barry Scheck later returned during the rebuttal phase to attack Deedrick's credibility on fabric imprints and an undocumented observation about knife damage to Ron Goldman's shirt.