It seems to me that the pillow over the face is a mistranslation of the statements that AK gave overnight Nov. 5-6 2007, right before her arrest. In those statements, AK changed her account of her movements (that she was at RS' apartment the entire evening) to say that she ment her boss at the apartment because the bar she worked at was closed. She then said that her boss, Patrick Lumumba, want into Meredith's bedroom with her while Amanda stayed in the kitchen, and she vaguely remembered him killing her. I have linked to a site to download both statements in a previous post.
Amanda retratacted these statement in a note 1 pm that afternoon and continued to maintain that she was at RS's apartment since then.
Edited to add: If you are in the US, 20/20 will be doing a story on the case tonight. I expect that they will have a pro-innocence slant but it will probably be a good primer on the basics of the case.
To see the not-guilty arguments, I recommend
Injustice in Perugia.
Pro-guilty arguments can be seen at Perugia Murder File. This site split into two a few months back, but they have similar information. Link here:
PMF.org or
PMF.net