Her father was the first witness called by the prosecution. William Bach was the first witness to take the stand during Tuesday's trial.
"He couldn't look me in the eyes," William Bach said. "I felt suspicious."
That's the way William Bach described a face-to-face conversation he had with McCowan hours after his teenage daughter went missing in the early morning hours of September 16, 2011 from Union Township, Indiana, just outside Valparaiso.
It's taken nearly a year and a half for this case to come to trial. McCowan stands accused of murdering his on-and-off girlfriend. The case has attracted a lot of attention. McCowan is the son of a Crown Point police officer.
Amanda Bach's body was found the next day alongside train tracks just 300 yards from McCowan's home. She'd been shot once in the neck.
From the start, McCowan said Amanda Bach had been with him prior to going missing, but denied any involvement in her disappearance. During opening statements, prosecutors said they have evidence that proves McCowan shot Amanda Bach with his father's missing gun, then dragged her body to where it was found.
But defense attorneys said there was "gross negligence during the investigation.... Police assumed it was Dustin and never looked back."
Defense attorneys also pointed out that there is no physical evidence, DNA or otherwise, that links McCowan to the murder.
Relatives for both McCowan's and Bach's families left the courthouse without comment.