The preliminary hearing opened on December 11, 2006, with Reiser being represented by attorney William Du Bois. At the hearing, a forensic technician testified that blood matching Nina Reiser's DNA had been found on a bag in Hans Reiser's car, and on a pillar in his mother's (Beverly Palmer's) house, where he had been living since the separation. It later emerged that a mistake had been made when the police analysed the blood on the pillar, rendering the evidence inconclusive. Police also testified that they had found a 40-piece socket set which may have been used to remove the passenger seat, a receipt for the purchase of the socket set from Kragen Auto Parts, four seat bolts, and a ratchet wrench with a socket on it, suggesting that the seat may have been removed recently. A traffic officer who had pulled Reiser over nine days after Reiser's wife went missing testified later in the trial that the passenger seat had been present at the time, and that he had not seen any blood.