By Mike Hellgren

BALTIMORE (WJZ) — A number of witnesses took the stand Thursday, as the trial got underway for Baltimore police officer Edward Nero. He is facing charges for the arrest of Freddie Gray, who later died from injuries suffered in police custody.

WJZ Investigator Mike Hellgren has more on the parade of witnesses who took the stand Thursday.

Rarely seen video from closed circuit cameras captured Officer Edward Nero with Officer Garrett Miller and Lieutenant Brian Rice on bike patrol at Gilmor Homes moments before Freddie Gray’s arrest.

Nero faces 15 years behind bars for his actions during the encounter with Gray.

As his trial opened, Nero’s defense argued he was just doing his job, and that Nero was not the initial officer to take Gray into custody, never touching him until he placed him in a seated position to find his inhaler.

Prosecutors believe there was never a reason for police to pursue or arrest Gray, calling it an assault.

“It was unjustified. And it was unjustified to even chase him like they did,” said Tessa Hill-Aston, NAACP.

“Was the search of Freddie Gray after he was initially detained legal or not,” said Warren Alperstein, lawyer and former prosecutor. “And the state alleges the officers had no right to actually search Freddie Gray.”

Prosecutors also made their case for the reckless endangerment charge, saying Nero ignored a new police policy issued just three days before the arrest, mandating officers seat belt all detainees in police vans.

“A violation of a police regulation does not amount to a criminal offense,” said Alperstein. “And that’s what I suspect will continue to be the defense’s theme.”

“I think it was an unlawful stop, an unlawful chase,” said Hill-Aston.

Prosecutors played a video showing an officer who’s about Gray’s size demonstrating how difficult it would be to move around in the van while shackled and placed on his stomach — the same position as Freddie Gray.

“You couldn’t have any closer contact with your wife then leaning over in that van and trying to seat belt these arrestees in,” said Warren Brown, lawyer and court observer.

Chief Deputy State’s Attorney Michael Schatzow said Nero needlessly risked Gray’s life.

“He leaves him face down on that filthy floor with his hands behind his back and his legs shackled,” Schatzow said in opening statements. “The issue in this case isn’t one of danger, it’s one of not caring.”

The prosecution has yet to call on controversial witness Officer William Porter, who’s also charged in connection with the case. The trial resumes at 9:30 a.m. Friday.