She didn't do it, she says, although buying the bleach and cleaning up the blood certainly makes me question this gorgeous pussy's words....
Sometimes, people tried to erase evidence out of paranoidity, even if they are not guilty. Imagine for example one day as you were jogging in a forest, you found someone laying on the ground facing down. You thought that the person faint or something, so you tried to turn his body to face you, but you found that the person was stabbed in his chest, but still alive. So out of spontaneity, you took out the knife and tried to stop the bleeding, but then the person died. Now you have blood everywhere on your hand, and your DNA was on the knife's handle. What would you do in that situation? Now there was a possibility that you might become the suspect of the murder. You could either call the police and took the risk to be suspected, or you could try to escape, maybe you throw the knife to a nearby river to damage the fingerprint, then you wash your cloth and take shower and pray that police wouldn't look for you. Just an example :shrug:
In this case, what happened if she (Knox) entered the house in the night of the murder, entered the bathroom (and stepped on the bloody floor without realizing it) and realize later when she saw her bloody footprint everywhere in her own bedroom's floor? She probably then checked where did the blood came from and when she opened the victim's room, she found the body. She was afraid to enter the crime scene and called her boyfriend to ask what to do. As she was at the crime scene with bloody footprint, maybe then her bf said, let's clean up everything tomorrow before we call the police. This could explain why the bloody footprint of Knox's shoes were found in her room and in the bathroom, but not in the victim's room.
Alternatively, it might also happened that the actual murderer (let say for example that other guy, Guede) staged the footprint. Police said they found the footprint which matched Amanda shoes (#37), but isn't it possible that the murderer used her shoes to divert the blame? Then when she found out that there was bloody shoes footprint in her room and in the bathroom, maybe she then try to clean it with the bleach out of fear she would be suspected for something she didn't do?
I mean, it is a mistake to cover up evidence, but doesn't mean that someone is guilty. If she indeed innocent but covering up the evidence, she should be held responsible for lying.