A Broward Sheriff's Office surveillance technician was the first person to testify on Day 2 of the Parkland school shooting sentencing trial Tuesday.
Technician Ron Lowther said he took six hours of surveillance video from the Feb. 14, 2018 shooting at Marjory Stoneman Douglas High School and edited to show the path Nikolas Cruz took during the shooting.
"I was able to put together a sequence [of videos] that follows the subject from camera to camera," Lowther said.
Cruz, now 23, pleaded guilty in October to 17 counts of first-degree murder and 17 counts of attempted murder in the shooting.
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A jury will decide whether the gunman gets the death penalty for the shooting or life in prison.
The trial began Monday with opening statements from lead prosecutor Michael Satz, who described how the gunman coldly mowed down his victims as family members in the audience wept.
After defense attorneys reserved their openings for later in the trial, the first witnesses were called to testify.
A teacher and two former students recalled the horrors they experienced on the day of the shooting and prosecutors played audio and video clips from classrooms and hallways at the school in which gunshots, fire alarms and screaming could be heard.