FORT MYERS, Fla. - Former school resource officer Scot Peterson was arrested Tuesday in connection with his inaction during a mass school shooting, 15 months after a shooter killed 17 people at Marjory Stoneman Douglas High School.

According to Broward County Sheriff Gregory Tony, Peterson and Sgt. Brian Miller were found to have neglected their duties during the Feb. 14, 2018, shooting in Parkland.

“We cannot fulfill our commitment to always protect the security and safety of our Broward County community without doing a thorough assessment of what went wrong that day,” Tony said. “I am committed to addressing deficiencies and improving the Broward Sheriff’s Office.”

The pair have been terminated.

Peterson, 56, was arrested in Broward County on seven counts of neglect of a child and three counts of culpable negligence and one count of perjury. The arrest comes after a 15-month investigation into the actions of law enforcement following the shooting.

Peterson was taken into custody and booked into the Broward Sheriff's Office's main jail.

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“The FDLE (Florida Department of Law Enforcement) investigation shows former Deputy Peterson did absolutely nothing to mitigate the MSD (Marjory Stoneman Douglas) shooting that killed 17 children, teachers and staff and injured 17 others,” said Commissioner Rick Swearingen. “There can be no excuse for his complete inaction and no question that his inaction cost lives.”

Peterson was the school resource officer during the school shooting.

The investigation shows Peterson refused to investigate the source of gunshots, retreated during the active shooting while victims were being shot and directed other law enforcement who arrived on scene to remain 500 feet away from the building, FDLE reported in a news release.

FDLE agents interviewed 184 witnesses, reviewed countless hours of video surveillance, and wrote 212 investigative reports totaling over 800 hours on the case, a news release indicated. FDLE agents received the full cooperation and assistance from the Broward County Sheriff’s Office, Coral Springs Police Department and all other agencies that responded to the school shooting.

"All the facts related to Mr. Peterson’s failure to act during the MSD massacre clearly warranted both termination of employment and criminal charges," Tony said. "It’s never too late for accountability and justice."

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