I just thought I'd add a little to the question of crime scene processes.. From what I thought the tape should go up immediately. However I thought about it, and it was mentioned that the Police declared the house a crime scene on the Fri and executed crime scene warrants. I am going to share a link, that although it relates to NSW police powers, gives a general idea.. It may be and probably likely that as stated the Police declared a crimes scene on the Friday.. Police can as stated below declare a crimescene when they suspect a serious offence, this declaration can last a numbr of hours and they then may in that time apply for a warrant and this is usually then an extension of the initial crime scene declaration..so Perhaps the tape not going up until The Saturday may have been when they got official crime scene warrants..JMO Hope I haven't done too much quoting, thought it may have been of interest including some of the powers police have when a crime scene warrant has been executed....
Queensland Police Powers and Responsibilities Act
Part 3 Crime scenes
Division 1 Establishment of crime scenes
(3) The responsible officer may establish the crime scene in any way that gives anyone wanting to enter the place enough notice that the place is a crime scene.
Examples
1 A police officer may stand at a door to stop people entering a building and tell them they can not enter the building.
2 A police officer may put around a place barricades or tapes indicating the place is a crime scene.
3 A police officer may display a written notice stating the place is a crime scene and unauthorised entry is prohibited.
Division 2 Crime scene warrants
166 Responsibility after establishing crime scene
(1) As soon as reasonably practicable after the responsible officer establishes the crime scene, a police officer must apply to a Supreme Court judge or magistrate for a crime scene warrant.
171 Consideration of application and issue of crime scene warrant
(1) Before issuing a crime scene warrant, the issuer must have regard to the following
(a) the nature and seriousness of the suspected offence;
(b) the likely extent of interference to be caused to the
occupier of the place;
(c) the time, of not more than 7 days, for which it is
reasonable to maintain a crime scene;
(d) any submissions made by the occupier.
[
B](2) The issuer may issue a crime scene warrant only if reasonably satisfied the place is a crime scene[/B].
(3) If before the application is considered, the place stops being a crime scene, the issuer may issue a crime scene warrant that has effect only for the time the place was a crime scene
http://www.legislation.qld.gov.au/LEGISLTN/current/P/PolicePowResA00.pdf