Okay, figured I'd give us something to do....
If I was Inspector Ainsworth I'd be dividing my team up into groups of two-three and giving them a 'theory' to prove re what happened that night, then do a big
'show-n-tell' where the other detectives get to pick their theory apart.
So.... here's my theory of what happened.
Allison and GBC have a volatile relationship and DV is a regular part of the household. As previously stated by a websleuth member, GBC depises Allison for seeing him for who he really is. BUT he DOESN'T want out of the marriage - it suits him to be a married man.
Things however are heating up for GBC.... the business is about to go under - he owes a whole lot more than what we've heard about. People he's lent money from are starting to put some pressure on. TM is also putting the pressure on and he gives her a commitment re July 1. He has no intention of keeping it, just silencing her for the time being. His past (all in my theory of course!) is littered with shady deals skirting the edges of legality. Possibly he's tipped over into fraud. His other mistresses are also placing some pressure particularly one who threatens to spill the beans to both Allison and TM. He's feeling boxed in. I would suggest he has trouble seeing a way out of this mess he finds himself in.
He brainstorms some theories.... What would happen if??? The idea of getting his hands on Allison's insurance money passes his mind... he fantasises about how he would do it. He makes some queries about the insurance, but consciously discounts the idea.
The night before that fateful night he and Allison have a big fight. Possibly police are called (thus why they open a missing person investigation so quickly). Allison has found out the affair with TM is ongoing and she has had enough. She is more vocal in standing up for herself than ever before. Now she is no longer trying to save the marriage - and he senses it.
The night of the 19th GBC has a headache after arguing with TM. Allison comes home from the hairdresser, collecting the girls from Nigelaine on the way. She prepares the girl's lunches and clothes for the next day and puts them to bed. It's about 8:30pm. The girl's have gone to bed after a certain show they were watching on tv has finished (thus why QPS want scheduling info). A fight starts. ABC runs into the yard to get away from him... she wants some space, he follows - poor little dog next door complains loudly. Possibly GBC drags Allison back into the house by the hair.
She has really had enough. She tells him that she's sick of all this. He can get out. She gives him till the end of the weekend to go. If he doesn't she'll start telling everyone what he's REALLY like - "what will Mummy think of him then?" she asks.
He disappears into their bedroom, she decides to calm down by having a warm bath. Without putting much thought into it, he decides his ONLY option is to 'get rid of her'. He goes into the bathroom and strangles her. She puts up a fight, chipping her tooth and submerging several times in the struggle. It's still early in the evening... around 10pm possibly. He moves her to the bedroom in case the girls wake and go to the bathroom, and he dresses her. He wraps her head in a plastic shopping bag as there is a bit of blood and he doesn't want it leaking.
At some point he rings Daddy. Whether it's here or further on I'm undecided. He tells his father that there was an argument, Allison was being unreasonable and pushing him around - he pushed her back, she hit her head and died. Daddy is led to believe it's been a horrible accident but GBC convinces his father that it would be better for the girls if the world believed it was a random stranger than their father who did the deed. NBC agrees and they decide to tell EBC (and possibly Olivia) that ABC has 'taken off' in a depressed state and GBC is frantic about her. EBC says that they can't possibly go off to look for ABC leaving the girls alone in the house so she insists on going over to sit in the house. Tricky for GBC because he now needs to get the body out of the house by himself. He wraps Allison in a blanket and bundles her into the back of her car. A passerby notices all four doors open.
He quickly dumps her body somewhere... anywhere relatively secluded (he knows they'll come back and move it) and heads to a local roundabout to collect EBC and take her to the house. He has convinced his parents it wouldn't be good for their car to be seen at his place and to keep it hidden in the carpark or behind the bus shelter. He goes the long way around because it would be natural instinct for him to stay away from the road where he's just dumped Allison's body.
EBC sits at the house. Possibly one of the girls wakes to go to the toilet and tells the nice policeman the next morning about nanny being over the night before. GBC collects NBC who collects the other BC car as they tell EBC they will go in different directions to look for Allison. Instead they head to where GBC has left her. NBC decides on where they will take her and together they work on a story. She was depressed, she took off in her car.... maybe she suicided or was attacked by a random person. Whichever, they plan to leave her car. Their plan comes unstuck when they see the trail of blood that has dripped down from the plastic. They are going to have to take the car home and wash it.
They return to the house with the excuse that they are too tired to search anymore. GBC perhaps tells EBC that he's had a text from Allison and that she's staying with a friend overnight. He drops EBC and NBC back at the roundabout then heads home to clean up. He suddenly remembers something and calls NBC. He and NBC have buried the blanket somewhere far away from where they've left Allison and the BC house.
He cleans the car, and checks to make sure there aren't any blood stains etc at home. He heads to bed.
In the morning he sends the two texts to Allison, which I believe to be one of his biggest mistakes. He wants to 'show' police her phone (and his) have the 'find my phone app' (because he's cleverly left his phone at home the evening before (he's used to tricking Allison with the Iphone app after all). He has left her phone somewhere away from her body and the blanket. Instead of calling around her friends and parents, instead of calling her instead of texting, instead of putting the girls in the car to go and find her.... he rings police to report her missing. Max Sica made a big mistake in his 000 call, and so did GBC I believe. GBC called too early.
Because this all unfolded so quickly he googles self incrimination and reads about maintaining silence. He calls NBC and tells him it's best if all of them (Olivia included if she was in the Nigelaine house that night) make no comment to police. They know it will be up to police to prove involvement, much easier if they aren't given a statement to disprove first.
When police arrive he spins a yarn of depression. He says he went to bed and didn't know when she went missing. He explains the marks away. Police ask if she was getting treatment for the depression -he can't remember her therapist but googles the name for the police. Police are suspicious (face scratches, previous DV, comment by child, lack of 'looking' before calling them) and open a missing person investigation.
GBC thought he was going to get away with it. He didn't realise a facetime call was traceable. He didn't realise putting the phone on the charger was traceable. Perhaps he told TM something.... but she spills anything she knows to police. Perhaps it's not about the murder but possibly fraud issues.
What really 'cooks his goose' though is Olivia confessing to police that he had gone looking for Allison the night before. She is the weak link in the family that didn't keep quiet. But she didn't think it would really matter because she truly believed her brother's innocence.... after all her father was with him searching... wasn't he??? The bail hearing shattered Olivia's existence - it's just starting to dawn on her what really happened. EBC fully believes the yarn her husband and son have fed her. As GBC feel the police closing in, he makes other plans. It wasn't about the insurance, but if he can get the insurance money he can flee the country and leave everything and everyone behind. He organises fake documents and starts preparing the groundwork. Maybe this is what TM told the police - maybe he was taking her with him. But she fully believes, as does his mother and sister, that he is innocent.
GBC is devastated when charged. He realises that TM and Olivia have 'dropped him in it'. He desperately tries all legal avenues for new ideas. He can't talk to Mummy or Daddy. He is a trapped lion, just like the ones his father used to hunt in Rhodesia.