Gregory Keau, a former McKinley High School educational assistant, has been sentenced to 10 years in prison for sexually assaulting a mentally disabled female student at the school in 2007 and again this year.

Prosecutor Thalia Murphy asked that Keau be sentenced to 22 years behind bars for what she called "outrageous" conduct that will affect the victim for the rest of her life.

Defense lawyer Lee Hayakawa asked for probation for his client, saying he has "a teachable spirit" and that he is "worth saving."

Circuit Judge Michael Town ordered Keau, 30, to serve 10 years in prison.

"You crossed the line," Town told Keau.

Keau committed "an egregious breach and betrayal of trust," the judge said.

Murphy told Town that in addition to assaulting the student, Keau infected the victim with a sexually transmitted disease.

The victim is an immigrant from the Marshall Islands. Her grandmother, who adopted the child as her own daughter, told Town in halting English that the young woman "is not the same girl as she was before."

The victim "has scary nightmares," she said.

"My husband and I try very hard to help her in every way we can but it's very hard."

Murphy noted that Keau had a minor criminal record when he went to work as an educational assistant at McKinley and wondered how he could have been hired.

He was convicted of misdemeanor charges of assault and violation of a protective order and had received a deferred sentence of guilt after pleading no contest to a disorderly conduct charge, Murphy said.

Keau's mother, also an educational assistant at McKinley, spoke on her son's behalf and said she helped him get the job at the school.

"I'm the one that got him hired," said Cherylann Makilan.

"I'm happy he took responsibility" for his crimes by pleading guilty, she said in court.

Keau told Town he was "extremely sorry for my illegal, immoral and unethical actions."

He apologized to the victim's family and to his own family.

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