BOSTON (WHDH) — Ariel Castro spoke at length Thursday in the courtroom and experts said it gave insight into his state of mind.

Jack Levin, a criminologist from Northeastern University analyzed the Cleveland kidnapper’s statements to give perspective on how a person like Castro sees himself.

"He is a monster. He has a character disorder. He has no conscience. He doesn't feel remorseful when he does the wrong thing. He doesn't empathize with victims,” said Levin.

In court, Castro tried to defend his actions and said the sex was consensual, the FBI didn't do their job, he was addicted to porn, and that it wasn’t his fault.

"This was a message that he gave to other people. He didn't have to justify it to himself because he lacked a conscience. He wasn't remorseful in the least. But for 10 years he fooled everybody. And he tried to do the same thing in court. And it didn't work,” Levin said.

Castro also tried to deny that he killed his unborn child by beating one of his victims. The judge didn't buy it, and Levin said you shouldn't either.

"He took no responsibility for his sexual torture. He took no responsibility for the way he actually killed an unborn child. Nothing was his fault. He was an addict. He was a victim,” said Levin.

Join our Newsletter for the latest news right to your inbox