Natalia, a friend of John
Suspected because she already have a long criminal record : stealing, vandalism, bullying...
Her story: She spent most of the time in the living room for the party. She only tried to go upstair once to go to the bathroom. But as she was in the stairs, she heard six gunshot. She stayed a moment here, paralyzed with fear. The she went back to the living room to tell her friends.
I don't trust her!