Nikolas Cruz, 19, has been charged with 17 counts of premeditated murder over the shooting rampage at the school that expelled him last week.
The teen is accused of massacring 17 people with a semi-automatic rifle at Marjory Stoneman Douglas High School in Parkland on Valentine’s Day.
Looking sullen and keeping his head bowed, Cruz, wearing a red prison jumpsuit, sat virtually motionless as the judge and his lawyers discussed matters relating to his trial.
Flanked by heavily armed guards, Cruz stayed silent throughout the “status hearing” in Fort Lauderdale, reacting to questions only with slight nods.
His legal team filed a motion to keep certain documents relating to his defence sealed from the public on Friday.
Judge Elizabeth Scherer agreed to uphold the ruling to keep the documents sealed but stressed she was in favour of transparency wherever possible.
The sealed document is about “access” to Cruz, according to judge, though she did not disclose its full contents.
His defence also signalled their intent to keep future documents under seal.
Cruz is yet to enter a plea but is understood to be contemplating admitting guilt if the death penalty if waived.
However, court documents reportedly showed Cruz has already confessed to the shooting – one of the deadliest in US history.
He told authorities he was “the gunman who entered the school campus armed with a AR-15 and began shooting students that he saw on the hallways and on the school grounds”.
Cruz has been characterised as a “troubled” teenager who became “depressed” after the death of his adoptive mother in November last year.
Meanwhile, the “shocked” family who put a roof over his head after his mother died have spoke of their disgust at his alleged mass shooting.
James and Kimberly Snead, who live in Parkland near the school, are perplexed over his transition from “naive” boy to alleged killer.
“We had this monster living under our roof and we didn’t know,” Ms Snead told the South Florida Sun Sentinel. “We didn’t see this side of him.”
Cruz still lived with the Snead family when he slaughtered students and teachers with an AR-15 rifle he bought legally.
“Everything everybody seems to know, we didn’t know,” James Snead said. “It’s as simple as that.”
In the wake of the shooting, US President Donald Trump has signaled increased regulation on gun ownership could be on the table.