Ema cannot imagine what it's like to kill someone.
She can't, no matter how she tries. She lies in bed the night after the first day of the trial—the chilly, empty house that she'd let herself into with her key—and tries. She lets into her mind the picture that Angel Starr had painted in court, lets it in after trying so hard all day to keep it out. She mouths words at the dark ceiling that had echoed in the courtroom: Stabbed him in the chest. Blood on the defendant's coat. Plunged it in over and over.
She raises her hand above her face in the dark, and wraps her fingers around the hilt of an invisible knife. She does not move the hand in a mimic of stabbing—she cannot make herself. But she pictures as precisely, as scientifically as she can, ramming the knife into a person. She wonders if it would break the ribs, or slide between them. She imagines blood splattering on clothes and face. Detective Goodman's blood.
No. She can't imagine it. Her mind rebels, hastily erasing the picture, so she stops trying to see the moment of violence and focuses only on the fact of death.
Mr. Goodman is dead. She squints at the ceiling, straining to understand that completely. Mr. Goodman is dead. He is never going to walk again, or breathe, or clock in for the day at the police station. He is never going to pass by her waiting outside her sister's office and say, "Hey there, squirt. How've you been?" He is cold, and dark, and still. She imagines herself making that happen. She imagines her sister making that happen.
No. She decides for the one millionth time that it is impossible. Her sister… would never. Could never. She doesn't care how unscientific it is. She just knows. So she turns over and goes to fitful sleep, knowing that she will probably wake in a few hours and have to make it one million and one.