Police claim Pakenham was coming down from P, had smoked a couple of cannabis joints and had been drinking bourbon when he claimed he tried to stop Ms Niethe from driving away from his house.
The next day, police say, the labourer went to Ms Niethe's Kerepehi home and gave some of her belongings to her daughter as her family searched for her, worried because she hadn't come home and hadn't answered phone calls.
According to the police summary, Pakenham allowed officers to examine his home, but their inquiries found no clues.
Pakenham would later tell the Herald that he went to church to pray for Ms Niethe and her safe return.
Ms Niethe had earlier borrowed her mother's Honda Civic hatchback car on the afternoon of March 30, 2003, not saying where she was going but that she would be away for several hours.
Just before 2pm that day, she bought a bottle of bourbon from the Ngatea Hotel and cigarettes and pre-mix drinks from the Ngatea Service Station.
Later that afternoon, one of Pakenham's previous partners drove past his home and saw Ms Niethe's Honda parked in his driveway.
The following afternoon, Pakenham went to Ms Niethe's home and found her mother, Eileen Marbeck, had started looking for her daughter.
Pakenham spoke to Ms Niethe's eight-year-old daughter, Simone, and handed her sunglasses, a phone, cigarettes and a cigarette lighter saying Ms Niethe had left them at his home when she left.
Pakenham acknowledged Ms Niethe had been at his home on the afternoon of her disappearance when police spoke to him on April 3, 2003.
He claimed the pair had drunk most of the bottle of bourbon and that she had smoked two cannabis cigarettes which he also shared before they had sex later that night.
He said Ms Niethe then started acting like she was really "pissed" and they began arguing as she wanted him to drive her home.
He said he didn't want to because he had been drinking and he tried to hold her back from going to her car.
They had a "brief struggle" - which Pakenham said was not violent - before he let her go. He then heard the car being started and driven away.
The whereabouts of Ms Niethe's body and the Honda Civic car remain a mystery despite many searches and a $50,000 reward for information.
Pakenham will re-appear for a post-committal conference on December 2.