Sixteen-year-old Vernon Bartley could spend the rest of his life in prison following his indictment yesterday on a charge of first-degree murder.

Bartley "attacked, raped, strangled and murdered 51-year-old Karen Ertell" in May 2007, First Deputy Prosecutor Douglas Chin said after a grand jury returned the indictment.

The first-degree homicide count was filed against Bartley because Ertell, a neighbor of his family in 'Ewa Beach, was scheduled to testify against the teenager in a pending burglary case, Chin said.

The charge carries a sentence of life in prison without the possibility of parole and is applied in cases involving the murder of a police officer, judge or witness in a criminal case, Chin said.

Bartley's lawyer, Jeffrey Hawk, was not available for comment.

Bartley was originally arrested and held as a juvenile, but Family Court waived jurisdiction in the case, allowing him to be prosecuted as an adult.

Chin said yesterday that his office could not use Bartley's juvenile criminal record against him in the murder case, but his office later said the pending burglary charge would be used in the murder case because Ertell was the complaining witness and had been subpoenaed to testify against Bartley when she was murdered.

Yesterday's indictment included additional second-degree charges of murder, rape and robbery, first-degree burglary and five other felonies.

Bartley is being held in lieu of $500,000 bail. Chin declined to say if Bartley is incarcerated at the Hawaii Youth Correctional Facility or at an adult facility. But he did say that the defendant has been segregated from adult offenders while in custody.

Ertell was the owner of Koko Crater Coffee Roasters in Kaka'ako. Her body was found in her home on May 25, 2007, after she failed to appear for work that day.

Neighbors and relatives immediately suspected Bartley. Ertell's foster daughter, Malanie McLellan, said Ertell had been served with a Family Court subpoena May 24 to testify against Bartley.

"It was calculated," McLellan said last year, adding that Bartley had repeatedly stolen from Ertell.

"The first time he stole $3, the next time bath soap, after that $600 and jewelry," McLellan said. "Things just escalated, but nobody thought it would escalate to murder. She gave him a chance to make amends by working in her yard and apologizing. She always thought there was good in everyone, but he never showed up."

Bartley was arrested at his home the evening of May 27 after his father called police to turn in his son, police said.

He moved to Hawai'i from New Zealand with his family in 2005, according to law enforcement officials.

Bartley's juvenile record here included more than 10 arrests for burglary, misdemeanor trespassing and misdemeanor theft, among other offenses, according to law enforcement officials.