Raymond Clark III was sentenced to 44 years in prison on Friday for killing Yale graduate student Annie Le.
The sentence came down after an emotional court appearance for Le's family, who traveled from California for the sentencing.
"You took away my only daughter," Annie's mother, Vivian Le, said in the courtroom. "I will never see any of her dreams come true."
Clark killed Le in September 2009, days before she was to get married, and stuffed her body into a wall at a Yale University research center.
Clark wiped tears from his eyes at Le's family members spoke and then his own father of his sympathy for the Le family and his love for his son.
"I stand here with unconditional love for my son," Clark's father said, but he made no excuses for what his son did.
Then, Raymond Clark III apologized to the grieving family.
"I have always tried to do the right thing and stay out of trouble but I failed," Clark said in court. "I stand here today to take responsibility for my actions. I'm sorry I lied and I am truly sorry for taking Annie's life."
Le, 24, was a graduate student who worked at the lab and Clark cared for the lab mice and cleaned the floors.
Annie's father, Hoang Le, and her brother, Chris, were also in the courtroom.
Chris said he hopes for greater security on Yale's campus and for safer working environments.
"The anguish I've felt over her loss is too much to comprehend," he said. "I know in my heart I can never forgive you."
Clark pleaded guilty to Le's murder under the Alford doctrine, which means he doesn't admit guilt, but concedes there is enough evidence to convict him. Clark also pleaded guilty to attempted sexual assault.
Le's uncle, Robert Nguyen, said Clark should get a death sentence and life in prison, at the least.
The agreement Clark reached calls for a 44-year sentence.
"This defendant will pay for his crime for the rest of his life," Judge Roland Fasano said.