To eliminate this possibility, the cops would need to turn that whole house upside down and did forensics on the uncluttered house (i.e. removed all the clutter outside of the house). I'm not sure if they did that or not.
Yes they did.
The judge had earlier warned them that police had completely emptied the house as part of their inquiries and although everything had been returned, it may not be in the same position or even the same room as before. The bath had been removed by the police during their investigation and had since been returned but not sealed in properly.
In addition, the house has also been subjected to extensive forensic testing, so jurors had to wear protective gloves and disposable overshoes while inside the property.
http://www.theguardian.com/uk-news/...ury-visit-alleged-murder-scene-accuseds-house