By Ian Bush, Oren Liebermann

CAMDEN, N.J. (CBS) — There was a guilty plea today from one of the teen brothers accused in the killing last year of a 12-year-old Gloucester County, NJ girl.

Camden County prosecutors say 16-year-old Justin Robinson told a Superior Court judge that he was solely responsible for the strangulation of Autumn Pasquale in October 2012.  He pleaded guilty to aggravated manslaughter.

“There will never be punishment commensurate with her brutal killing,” said Prosecutor Warren Faulk. “The best we can do is achieve some measure of justice.”

Doug Long is the attorney for Pasquale’s father, Anthony Pasquale.

“There’s never closure. His daughter is his daughter. She’ll always be missing from his life, but today was all about going through the process to make sure the defendant is paying for his crimes,” said Long.

Sentencing is set for next month, and he is expected to receive a 17-year prison term.

“The nature of the crime demanded Justin Robinson be sentenced as an adult and face adult penalties,” Faulk said.  The plea requires that he serve at least 85 percent of the time before he’s eligible for parole.

Robinson was just 15-years-old last October when authorities say he and his older brother killed Pasquale for her bike and dumped her remains in a recycling bin next to the Robinsons’ house in Clayton, NJ (see related story).

Due to what prosecutors said was “limited” forensic evidence in the case, “proving Justin Robinson’s guilt beyond a reasonable doubt without his admission in court today that he was her killer would have been difficult,” Faulk said.

“I think it’s clear that the main perpetrator has plead guilty in this case,” said Jaime Kaigh, the attorney for Pasquale’s mother, Jennifer Cornwall. “I’m satisfied. The family is satisfied through discovery and discussions with the Camden County Prosecutor that the right person has been waived to adult court, pled guilty, taken full responsibility.”

Early this year, the case was transferred to Camden County after the Pasquale family filed a lawsuit against Gloucester County prosecutors over the initial handling of the investigation.

Officials say today’s hearing dealt solely with Justin; charges against his brother, who is 17, are still pending in juvenile court in Gloucester County.

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