At another point when Curcio left the room, he repeats over and over: "Why didn't he kill me?"
During the more than 11 hours of questioning by Broward sheriff's Detective John Curcio, Cruz usually answered in short sentences or nodded yes or no, speaking so softly that the detective repeatedly told him to speak up.
Last week, the Sun-Sentinel released a report about Cruz's time in the general population at Marjory Stoneman Douglas High School, which found that Cruz had requested to be placed in a special education school, but that school officials "did not follow through".
Detective asked if he was expelled "I just stopped going and then transferred me". Why didn't he kill me?
According to a CNN report, Cruz told detectives that he had heard a demon's voice in his head that compelled him to commit the violent act.
Cruz, 19, is charged with 17 counts of murder and 17 counts of attempted murder in the assault on Marjory Stoneman Douglas High School in Parkland on Valentine's Day. He did not resist arrest.
Cruz is accused of killing 17 students and faculty at the school in Parkland, Florida. His public defenders have said that they would accept a deal from prosecutors to send Cruz to jail for life.
Cruz's attorneys, however, have painted the confessed shooter as an individual with severe and complex psychological problems. "If you have anyone to blame it's me".
He told Curcio that he had to fight the voice from taking over, that it was always bad. "Because I have no one", he said.
He added that the demon told him to "burn", "kill" and "destroy". "At the end you are nothing but worthless, dude", he mumbled to himself. Later he refers to himself as a "coward".
Cruz told the detective that he planned to shoot people at a park the week before, according to the transcript. Cruz, who worked as a cashier at a Dollar Tree and had inherited money from his mother when she died four months earlier, estimated the collection had cost him about $4,000.
"They talked to the students, they talked to the parents at my school and most of us agreed that this was the right thing to do", Ho-Shing said. Cruz couldn't remember exactly, but he didn't want to do it. Curcio asked why he didn't.
When the detective asked him why he had made a decision to buy a semiautomatic rifle - an AR-15 - the one he allegedly used in the massacre, he replied: "Because it looks 'cool'". "And then it's me".
When the officer briefly left the room to look for water anyway, Cruz said to himself: "Kill me, just kill me".
The detective asked Cruz what the demon told him to do. The inaccuracies reportedly led Cruz to ultimately reject special education services in a therapeutic environment when, at 18, he signed a form stating he would give up special services to remain a regular student at Douglas.
Curcio told Cruz he doesn't believe the voice exists, but Cruz insisted it was there and said he wanted to see a psychiatrist.