William Thompson was a defense attorney identified in the record as a DNA expert and UC Irvine professor. In March 1995, he appeared before Judge Lance Ito with Robert Blasier, Peter Neufeld, and Barry Scheck, and he later participated in proceedings concerning DNA-evidence admissibility, DNA-mixture interpretation, and DNA statistical evidence. On June 22, 1995, Thompson examined Dr. Bruce Weir and conducted the direct and redirect examinations of Dr. William Shields.