A Florida judge earlier this week agreed with news outlets including The Associated Press that the video should be released.
Video shows deputy outside school
The video from outside the school depicts actions during the shooting by former deputy Scot Peterson, who was armed and assigned to the school but did not enter the targeted building during the shooting. Broward County Sheriff Scott Israel said Peterson was suspended without pay, and chose to resign.
Police and school officials had resisted the release, saying it was evidence in an active investigation. Video of what happened inside the school is not being released.
The surveillance video shows Peterson outside the school, at times running and talking on his radio, at other times on a golf cart. Peterson and another deputy are then seen apparently taking up a position behind a building. He is not seen entering the school.
In a statement along with the video release, Broward Sheriff's officials said they "welcomed" the court's decision to release the video.
"The video speaks for itself. His actions were enough to warrant an internal affairs investigation, as requested by Sheriff Scott Israel on Feb. 21," the statement said.
Israel said last month that the video shows Peterson arriving at the west side of Building 12 and taking up a position, but he "never went in" as shots rang out inside. Israel said Peterson "clearly" knew there was a shooter and was outside for about four minutes. The shooting lasted about six minutes, Israel said.
When asked what the deputy should have done, Israel said, "Went in, addressed the killer, killed the killer." Israel said he was "devastated, sick to my stomach, there are no words."
Speaking for Scot Peterson, lawyer Joseph DiRuzzo last month that the one-time school resource officer of the year didn't go inside the high school because it sounded like the shooting was happening outside the building. DiRuzzo called the criticism of Peterson's actions unfounded and described them as "uncalled for attacks upon his character."
Nineteen-year-old Nikolas Cruz faces 34 murder and attempted murder charges in the attack. He appeared in court Wednesday as students across the nation walked out of school to protest gun violence.
Cruz said nothing during a brief hearing. Because he refused to announce his plea, Circuit Judge Elizabeth Scherer entered a not guilty plea on his behalf - mainly to keep the legal process moving.
His attorney, Assistant Public Defender Melisa McNeill, reiterated that Cruz would plead guilty if prosecutors waived the death penalty, which they refused to do.
"They are bleeding:" More 911 calls released
While Cruz sat in the courtroom, more details of the shooting emerged as the Coral Springs Police Department released recordings of 911 calls and police radio traffic.
In the recordings, students and dispatchers were uncertain about the shooter's location and how to hide from him.
Some were frightened the gunman would return to their location when asked if they could perform CPR on the wounded.
"Please, please, please, there are people here. They are bleeding. They are all going to die," a teenage girl calling from classroom 1215 said through tears and heavy breathing. "There's a lot of people around us that are injured, people that are injured, people that are bleeding. He is upstairs now."
A teacher from room 1216 also called for help and told the 911 operator that a student had been hit in the chest, and wasn't breathing.
"He's twitching. There's blood all over," she said.
The police radio recordings showed that the Coral Springs police officers were the first to enter the school building after confirming that Broward County Sheriff's Office deputies had not gone in.
As they cleared each of the building's three floors, the officers described seeing shell casings on the floor and bullet holes in the windows.
They warned that the suspect may have changed clothes after they reported finding a camouflaged jacket, ski mask and backpack on the first floor.
On the third floor, officers said they found an AR-15 with a magazine still attached.
The officers found wounded victims and bodies, and they prioritized evacuating the wounded before allowing other students and teachers to leave. On the third floor, they said they shattered windows in some locked classroom doors because terrified students would not open doors.
Cruz was arrested a few blocks away from the school.