I think if a person had planned to kill and dispose of someone, they would first and foremost take the person out of the house to kill them. No one has ever successfully cleaned up blood so luminol etc. doesn't find it.
If that was their plan then it was doomed from the start.
I agree with you to an extent - the risk of blood in a house is a real one and most murderers would plan to avoid that I think knowing the forensic capability of finding such evidence. But it can happen if the blood spilling wasn't foreseen by the perp 1) because it was not pre-meditated 2) they were planning to strangle or cosh their victim over the head but a struggle ensued and got messy, 3) they estimated that it would be easier to manage a murder there and then than to extract that person effectively and take them somewhere else to kill them or 4) it would be risky to plan to kill them in broad daylight out in the open - for instance in a park known to be frequented by runners. A house has the benefit of being shut off and private. Most of this assumes it was pre-meditated which I tend to believe and I also believe it likely that the perp was lying in wait for her in the house when she returned from the school run.
Currently I'm not sure whether the crime was planned by STXH and GF together, GF was probably involved at least either in transporting him to the house or in the clear up.
(By the way, given the charges against Dulos and GF I am now presuming that makes the involvement of a third party - hitman - less likely. )
The main question to my mind is how the perp planned to dispose of her and move her car. The options seem to be
- parking off-site on an adjacent road and walking through woods to get to the house and then using her car to move the body; being dropped off by someone else or leaving your own car/works vehicle at her house where she and others could have seen it. Of course other options like getting an uber is possible but would be very dumb!
If she was killed on premises then the options seem to be moving her in your own car and then coming back to move her car to the park; taking her body in the trunk of her own car for disposal before leaving her car in the park - this would still require them to be able to get back to their own car fairly quickly to get out of the area. Having to return to the house to move any vehicle would seem to be the least preferred option if this killing was planned. Unless there were two of them on premises to move two vehicles.
Given that both STBX and GF have been charged with tampering with evidence and hindering prosecution that to my mind puts them both at the house - if thats where the evidence was tampered with. Otherwise it could be disposing of her phone or moving her car or lying about some other details .
I'm sorry if I've made this sound more complicated! My main questions therefore revolve around:
1) was this planned together or alone?
2) was the crime committed together or by one alone?
2) the transportation of her body and moving of the cars
3) what evidence was tampered with and where.
In reality, it is perplexing for those of us who spend time on Websleuths - how did he think he was going to get away with it, being such an obvious prime suspect! Nevertheless, I'm hopeful that the GF will sing to save her skin.
JMOO - sorry to speak of Jennifer disrespectfully - I'd love to not think of her as a body being disposed of but an alive and happy divorced mother having fun and joy in her life. She clearly was doomed the moment she met him and deserved much much better as did her poor children and family. In truth the likelihood of him ever allowing her to simply move on without hassle or disruption post separation and co-parent their children was sadly very small to my mind, he was not going to make anything easy, he had to be in control. Even though he was happily esconced with his 'paramour' and her child. It must have been very stressful for poor Jennifer not seeing a way ahead for her and her children. Devastating.