HOUSTON, Texas (KTRK) -- During the fifth day of trial for Terry Thompson, the man charged in the murder of John Hernandez, a key witness in the case took the stand.
Ryan Staiger, the man who shot a viral cell phone video of the incident, was on the stand for hours Tuesday.
That video was introduced to the jury and played for the courtroom. Staiger told jurors that he felt that Thompson was not using "logical" force.
Hernandez's father spoke to Eyewitness News about his reaction to seeing and hearing the evidence presented in court.
"Yes. It's very difficult, and we feel very helpless that we were not there to help him, and that there were so many people around and no one stepped in to help either," the father said.
After Staiger's testimony, an expert who specializes in strangulation took the stand.
The expert used a mannequin to demonstrate the larynx, vocal cords and nerves in the neck.
Photos of Hernandez's autopsy were also shown - which prompted several of his family members to walk out.
The Denny's manager, who was on duty during the incident, is expected to take the stand Wednesday, once the strangulation doctor finishes.
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Day 5: Witness who recorded deadly Denny's fight testifies during trial