The girl was handcuffed and led to a police paddy wagon at her school in Tennant Creek in front of shocked students last Thursday.
The NT Police allege that the girl had committed several break-ins.
"My information, at this stage, is that the officers deemed it necessary to take that option," he said, "It's known in our policy as a last resort, often as a result of that person's violent behaviour," NT Police Commissioner Reece Kershaw told SKY News.
Commissioner Kershaw said the officers had no choice but to handcuff the school girl after she became aggressive.
"At this stage, I'm satisfied that the officer involved has given account that they believe their actions were proportionate to the violent history of that individual".