The Broward campus deputy widely lambasted for not entering Marjory Stoneman Douglas High during the massacre that killed 17 people insists he is no coward — and that he did not initially believe that gunfire was happening inside the building.

Broward Sheriff's Deputy Scot Peterson, in a statement released through his lawyer Monday, said his actions during the Valentine's Day massacre "were appropriate under the circumstances."

Peterson "heard gunshots but believed those gunshots were originating from outside of the buildings on the school campus," according to the release. "BSO trains its officers that in the event of outdoor gunfire one is to seek cover and assess the situation in order to communicate what one observes with other law enforcement."

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"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," according to the statement sent from the office of Fort Lauderdale attorney Joseph DiRuzzo.

Monday's statement comes four days after Broward Sheriff Scott Israel, in a stunning revelation, singled out Peterson for failing to engage school shooter Nikolas Cruz. The sheriff said Peterson waited outside Building 12 for four full minutes while Cruz continued the slaughter inside.

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Officers are taught to engage active shooters immediately and not wait for backup.

"I am devastated. Sick to my stomach. He never went in," Israel said during a news conference Thursday.

Hours before the press conference, BSO suspended the longtime deputy without pay, but he promptly retired. Peterson, a 32-year veteran, was named school resource officer of the year in Parkland four years ago.

In the statement, Peterson claimed he took up a position outside Building 12 after rushing over to respond to a report of firecrackers. He said that he was the first BSO deputy to dispatch on the radio that shots were being fired. He also claimed that he told a first-arriving Coral Springs officer that he "thought that the shots were coming from outside."

"Radio transmissions indicated that there were a gunshot victim in the area of the football field, which served to confirm Mr. Peterson's belief that the shooter, or shooters, were outside," according to the lawyer.

He also said he "had the presence of mind" to have school officials review with closed-circuit TV cameras "to locate the shooter."

The lawyer also ripped into Israel for prematurely criticizing Peterson, all while cautioning the public to wait for the results of a fast-moving investigation.

"Sheriff Israel's statement is, at best, a gross oversimplification of the events that transported," the statement said.

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