Background
6The following is taken from the evidence led at the trial. It includes some parts of the offender's evidence at the trial. Unless otherwise stated, the evidence was not disputed.
7The offender met Ms Rathbone sometime in 2005 or 2006. Within a few months she had moved into the offender's home. At that time the offender lived in a converted garage at the rear of his parents' home. They lived in that garage before moving to various other premises. There were two boys born of their relationship, Taylor born in xxxx 2008 and Robbie born in xxxx 2010. The relationship broke up in late 2010 to early 2011 while they were living at Rooty Hill and during a period in which the offender was not working. The offender returned to living in the converted garage and returned to work as a truck driver and forklift operator. Ms Rathbone stayed at the Rooty Hill residence with Taylor and Robbie.
8The offender described the initial period of their separation as amicable. He stated that despite their separation he and Ms Rathbone had sex once or twice per week. He stated that during this time they had an informal agreement whereby Taylor stayed with him in his converted garage one or two nights per week. The offender stated that he had little contact with his youngest son, Robbie, because "[h]e was only a baby".
9After a period, relations between the offender and Ms Rathbone deteriorated. There were a number of instances of conflict between them that were the subject of the evidence adduced in the trial, although the Crown and the offender relied on them for different purposes.
10On 31 March 2011 they quarrelled on the telephone about some parcels the offender arranged to have delivered to Ms Rathbone's home. The offender went to her house to pick up the parcels. According to the offender the visit descended into an argument about the parcels and about an exchange of text messages that had occurred earlier in the day. In one of those text messages the offender had said to Ms Rathbone "you just have the kids". The offender stated that he regretted sending the text message and asked her to delete it. He said that she refused and threatened to show the text message to their children. At some point the offender told Ms Rathbone that he would report her to Centrelink for residing with him while receiving a supporting pension.
11The argument that ensued culminated in the offender smashing Ms Rathbone's phone. Ms Rathbone responded by damaging his car, and the offender said he damaged her car in retaliation.
12After this incident Ms Rathbone replaced her mobile phone. She did not give her new telephone number to the offender, however he was still able to contact her via email.
13The offender did not see Ms Rathbone again until 5 April 2011. He went to her home at around 3am, demanding to see his children. The offender explained that the cause of the visit was his anxiety over a nightmare that he had in which their eldest son had been poisoned. Ms Rathbone refused him entry and threatened to call the police. Following that, the offender sent a series of facebook messages to Ms Rathbone's landlady threatening to report her and Ms Rathbone to Centrelink.
14The offender next saw Ms Rathbone on the evening of 7 April 2011. During that day they exchanged very friendly emails. It was arranged for Ms Rathbone and the two boys to visit the offender in the evening after work.
15The offender returned home from work at approximately 8pm on 7 April 2011. Shortly afterwards Ms Rathbone and their children arrived. They left after half an hour. One of the reasons they arranged to meet that night was to have sex, but that did not eventuate.
16The offender asserted that he did not eat on 7 April 2011, but instead consumed a large amount of alcohol from the time he returned home from work at 8pm until 3am the following morning when he went to sleep. I discuss the state of his intoxication later (at [44]).
17Early the next morning the offender was woken by his mother. After waking he telephoned his employer at 6.25am and told him that he would not be coming in to work that day. He said that he decided not to go to work because he thought he was "over the limit". He said that he kept drinking throughout the morning.
18From 7.30am the offender and Ms Rathbone emailed and telephoned each other. Following those exchanges she and Robbie went to the converted garage. In cross examination it was suggested to the offender that he and Ms Rathbone had arranged on the evening of 7 April 2008 to meet up again the following morning and have sex. The offender denied this, saying that they had arranged to meet up after his work when she would hand over the children, and he would look after them for the remainder of the weekend. The offender said that Ms Rathbone only came over that morning following those emails and telephone conversations. I accept that evidence. It is supported by an email bearing the time 10.03am but probably sent at 9.03am from the offender to Ms Rathbone stating "I'm home today; come over with Robbie". Taylor had been dropped at childcare shortly after 9am.
19The offender said that Ms Rathbone and Robbie arrived at 9.30am. Shortly after 10.30am they all walked to a nearby store. They were seen by a local shopkeeper.
20It was the Crown case that at some time after leaving the store, between 10.30am and 12.30pm on 8 April 2011, the offender bashed and strangled Ms Rathbone.
21He was next sighted at approximately 12.30pm leaving Ms Rathbone's home. In his evidence he said he went there to get a bottle of milk for Robbie. At 12.53pm, Ms Rathbone's neighbour, Mr Spencer Da Palma, received a text message from her mobile phone number which read "call me". Mr Da Palma called her mobile phone number. The offender answered and asked him "What is going on between you and Yvette?" Mr Da Palma replied "Nothing, nothing is going on". Later the offender rang him again from his own mobile phone, repeated the question and asked why his number was on Ms Rathbone's phone.
22The offender also attempted to call his mother. He made three calls at around 1pm. He then drove to ANZ's St Marys branch. At 1.23pm he withdrew approximately $8,500.00 from his savings account.
23At 1.50pm the offender spoke with his mother on his mobile phone. He asked her to go home. She asked "What's the matter?" He replied "I'll tell you when you come home. I'm sorry. You won't like it. I'm sorry". She again asked what the matter was. He said "I'm sorry, I will tell you when you get here. I can't tell you on the phone". The offender then drove to Taylor's preschool and signed his son out shortly before 2pm.
24The offender drove westwards towards the Glenbrook National Park. At around 3pm the offender purchased some beer from a liquor shop in Blaxland.
25In the meantime his mother had returned home. She did not find any one in the house. She went to the converted garage. She found Ms Rathbone's body lying on the floor parallel to the bed. She called her daughter to tell her what she had found. Her daughter called the police. At about 2pm two police officers arrived at the house. They found Ms Rathbone's body. There was a blanket over the lower part of her body and a pillow over her head. She was naked underneath the blanket. While the police were at the scene the offender rang his mother again. He said "I'm sorry, mum, can you look after the kids? I want to spend as much time as possible with them before I hand myself in to the police". He assured her the children were safe.
26The offender then continued driving to the Glenbrook National Park. Apparently he and his friends rode their bikes there when they were children. He parked and walked with the children to the lookout at Mount Portal. At around 4.30pm the offender called his long-time friend, Mr Benjamin Deller. Mr Deller said the offender was hysterical, could not get full sentences out and was very upset. He recalled him stating that he had killed Ms Rathbone and that he was apologetic and saying "she didn't deserve it". Mr Deller also said that the offender stated "he just strangled her, there wasn't a fight, there were happy moments before it, yeah". In his evidence the offender agreed that he told Mr Deller "I've killed Yvette" over and over and that "I think I have strangled her". He said he remembered seeing marks around her neck before he left the scene.
27After this call, the offender's brother called him and the offender told him "[s]he didn't deserve what I've done". Around the time of this call, at 4.38pm, a police helicopter began circling above the lookout. The helicopter filmed the offender and his two children standing on the viewing deck.
28The police arrived soon afterwards. They approached the offender. He was drinking a stubby of beer. After a short discussion the offender handed the two children over to police. At approximately 4.45pm he was arrested and taken to Penrith Police Station. He was interviewed in three sessions beginning at 7.36pm on 8 April 2011 and concluding at 3.23am on 9 April 2011. He was then charged.
29In R v Meyn (No 1) [2012] NSWSC 1441 ("Meyn (No 1)") I rejected a challenge to the admissibility of the offender's interviews with the police which was based on an assertion that the police had persisted in interviewing him, knowing that or reckless as to whether he was too intoxicated or exhausted to participate. I outlined the circumstances of that interview in Meyn (No 1) at [12] to [55]. I will not repeat them here. It suffices to state that in the first session the offender told the investigating officers that after Ms Rathbone came to the garage they put Robbie to sleep and had sex (A244). He said that after they had sex and while she was dressing he asked her "how she was goin[g] on PlentyofFish" which he said angered her (A248). "PentyofFish" is an internet dating site. The offender had found out she was seeking to meet people on that site by using a "dummy profile" (ie posing as someone else). The offender initially stated that he could not remember what happened next (A258) and that the next thing he could recall was her lying on the floor (A259). However in the last session the offender stated that he recalled an argument and an altercation in which she bit his chest (A511). He was asked about the blood on Ms Rathbone's head and he said "he might have hit her with something" (A562) and that he "might have choked her" (A565) but that he "didn't mean for her to die" (A567).