Assuming that the murderer is the person who cased Kylie's house, then returned minutes later after Kylie got home from shopping (then killed her), I think the intentions were pretty specific.
They didn't drive there (no vehicle to be traced/identified), they made an effort to disguise themselves, they didn't steal anything, they went during a period when Kylie was likely to be home and alone. They went to the home, looked inside (Kylie's not there), came back 10-15mins later when Kylie returned home (perhaps made a phone call? perhaps then waited nearby to see Kylie drive past on her way home?), then left 20 mins later (does that mean they were there for 5mins or 20mins? 20mins is a long time for a quick hit). Why didn't they just move on to a different house and enter that one instead?
"The Herald Sun has been told the man returned 10 to 15 minutes later, when Ms Blackwood had come home from a shopping trip and left the garage door open.
The tradesman has told police he saw the suspect "hurriedly" walking away about 20 minutes later."
http://www.heraldsun.com.au/news/la...-kylie-blackwood/story-fni0fee2-1226701849038
Did Kylie typically leave the garage door open during the day between school dropoffs? Did the killer know Kylie wouldn't be working that day? She only worked a couple of days each week .. were they the same days each week, or did they vary? Would Kylie normally have gone to pick the girls up, but didn't that day so they (unexpectedly) wandered home? Many articles say how impeccably dressed/groomed Kylie was when she was seen at the school. And Peter arrived home with the son 'shortly after' the girls discovered Kylie. Did Kylie typically drop off/collect the girls, and Peter dropped off/collected the son?
I must say, I am glad the non-local Homicide squad is investigating this crime, and not just the local police .. of whom one is also the Mayor! Small community, an everybody-knows-everybody situation, sometimes the hardest situation in which to pin down a murderer IMO.
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