Accused killer Vernon Bartley was meek and downcast until he was asked by police to describe the killing of his neighbor Karen Ertell, a detective testified in court yesterday.

Bartley "sat up in his seat" and physically re-enacted choking Ertell, said Honolulu Police Detective Theodore Coons.

"He was kind of reliving that. He smiled and he gave a kind of brief, silent laugh" when describing the murder, Coons said.

Bartley, now 17, is being tried as an adult on a charge of murdering Ertell, 58, his 'Ewa Beach neighbor, in May 2007, when he was 15 years old.

Bartley has pleaded not guilty to the charges against him.

Coons' testimony came during a hearing on a defense motion to suppress Bartley's confession on grounds that he did not understand his constitutional rights when he agreed to be interviewed by police about the crime.

Coons said he fully explained those rights to Bartley, whose mother was also present during the interview.

"I was surprised that Mr. Bartley made a statement," Coons told defense lawyer Jeffrey Hawk.

Asked why he was surprised, Coons said: "It was a heinous crime. I didn't think anyone would want to talk about it."

Circuit Judge Virginia Crandall reserved judgment on the suppression motion as well as another from Hawk for dismissal of a first-degree murder charge against Bartley.

That charge, which carries a punishment of life in prison without parole, can be filed only in cases involving multiple murders or the killings of police officers or witnesses in pending criminal prosecutions.

Ertell was to be a witness against Bartley in a pending burglary case when she was killed.

The burglary case was adjudicated in Family Court because of Bartley's age and Hawk has argued that such Family Court proceedings are not classified under the law as criminal prosecutions.

So the first-degree murder charge is legally defective and should be dismissed, according to Hawk.

In addition to first-degree murder, Bartley is also charged with second-degree murder, sex assault and seven other offenses, including robbery, burglary, car theft and credit card fraud.

Second-degree murder carries a punishment of life in prison with the possibility of parole. Trial in the case is scheduled to begin in mid-October.