He has been publicly branded a "coward" by the president of the United States and forced to resign his job in disgrace.
Now, after nearly two weeks of opprobrium, the sheriff's deputy accused of failing to take action during the Florida high school shooting is fighting back.
Scot Peterson, 54, broke his silence on Monday and defended his conduct during the shooting at Marjory Douglas Stoneman High School in Parkland, Florida, which left 14 students and three adult staff members dead.
"Let there be no mistake, Mr. Peterson wishes that he could have prevented the untimely passing of the 17 victims on that day, and his heart goes out to the families of the victims," his attorney, Joseph DiRuzzo III, said in a statement.
"However, the allegations that Mr. Peterson was a coward and that his performance, under the circumstances, failed to meet the standards of police officers are patently untrue," DiRuzzo added.
That Peterson was on campus and armed on February 14 when Nikolas Cruz, a troubled 19-year-old former student, opened fire on his classmates with an AR-15-style rifle is not in dispute.
How the more than 30-year veteran of the sheriff's office responded to the gunfire and what he could or should have done is where things get murky.
In suspending Peterson without pay last week, Broward County Sheriff Scott Israel made it clear he believed the deputy's actions were negligent.
Surveillance video showed Peterson arriving at the building where the attack took place about a minute and-a-half after the first shots rang out, Israel said.
Peterson remained outside the building for "upwards of four minutes," never going inside, he said.
Cruz fired between 100 and 150 rounds at students and teachers in a rampage that lasted about six minutes before he discarded his weapon and backpack and fled the school by blending in with other students.
'Killed the killer'
Asked what Peterson should have done, Israel said: "Went in. Addressed the killer. Killed the killer."
"When we in law enforcement arrive at an active shooter we go in and address the target and that's what should have been done," he said.
Peterson's attorney said Israel's description of the deputy's actions was a "gross oversimplification of the events that transpired."
"Mr. Peterson is confident that his actions on that day were appropriate under the circumstances and that the video (together with the eye-witness testimony of those on the scene) will exonerate him of any sub-par performance," DiRuzzo said.
Peterson was initially responding to what he believed were "firecrackers -- and not gunfire," he said.
After running to the building where the shooting was taking place, Peterson "heard gunshots but believed that those gunshots were originating from outside of any of the buildings on the school campus," he said.
"In the event of outdoor gunfire one is to seek cover and assess the situation in order to communicate what one observes to other law enforcement," he said.
Peterson took up a "tactical position," advised the Broward County Sheriff's Office that he heard shots and "initiated a 'Code Red' lockdown of the entire school campus," the lawyer said.
Peterson then gave his keys to a SWAT team so they could enter the building and provided handwritten diagrams of the campus to help with evacuation of students, DiRuzzo said.
'Coward'
Following Israel's comments, President Donald Trump attacked the deputy by name the next day, saying he either froze or was a "coward."
"They're trained, they didn't react properly under pressure or they were a coward," Trump said.
"When it came time to get in there and do something he didn't have the courage or something happened," Trump said. "But he certainly did a poor job."
Trump repeated his criticism of Peterson on Monday and suggested that he personally would have confronted the shooter.
"I really believe I'd run in there even if I didn't have a weapon," Trump said. "You never know until you're tested."
Peterson served as a "school resource officer" -- a member of law enforcement who provides security at a school -- for more than two decades.
He was named Parkland's school resource office of the year in 2014.
A YouTube video from several years ago shows the greying, heavy set Peterson testifying before the Broward County School Board.
In the video, he recounts how he once arrested four burglars who had broken into the school cafeteria.
"I ran into my trailer, I grabbed my firearm and my ID and my shorts and my sneakers and I ran over obviously to the cafeteria," he said.
"I chased them -- I'm getting older but I started chasing them," Peterson said, adding that he managed to eventually apprehend all four.
"We're all here for the same goal, to protect our kids, to protect our property," he told the school board.
