The victim of a vicious attack on Koko Crater said he’s "disgusted" by a court decision this week that will allow his assailant to attend college classes unsupervised.

Nicholas Iwamoto, 26, was stabbed 18 times and thrown from the crater rim by Benjamin Davis on Feb. 1, 2009. He broke his neck in the fall and fractured his skull. Although Davis was acquitted of attempted murder by reason of insanity, the state ordered him into the custody of the Hawaii State Hospital so he could receive mental health treatment.

On Tuesday, Circuit Judge Richard Perkins ruled that Davis could attend English classes without supervision at nearby Windward Community College.

Davis will be in classes twice a week for four hours, the Honolulu prosecutor’s office said. He also will be subject to a strict sign-in and sign-out procedure, random drug tests and a zero-tolerance policy for mistakes.

Iwamoto doesn’t agree with the decision.

"He doesn’t deserve to be out in the public," said Iwamoto, who is living in Boise, Idaho. "If he is better, if he is mentally healthy, he deserves to do his time."

When Davis was acquitted in 2010, several mental health experts had diagnosed him as schizophrenic and concluded that he lacked the ability to understand or control his actions when he attacked Iwamoto and another hiker, Guy Tanaka.

Davis said at the time that he attacked Iwamoto and Tanaka because he believed they were working for the government to kill him.

Iwamoto believed that Davis would never be freed.

"He is a ticking time bomb and the only way that the people of Hawaii will be safe from this man is if he is behind bars for the rest of his life," Iwamoto said. "Let him take English classes online."

Iwamoto’s mother, Kitty Iwamoto, said she was physically sick after hearing about the decision. She does not trust the medication that Davis is taking to keep his mental illness at bay.

"It just makes me nauseous," Kitty Iwamoto said. "It brings it all back. What my son went through and what we still go through, it’s like it is right there again."