Boy charged in sister's murder made prior threats: prosecutor

VALLEY SPRINGS, Calif. - In an argument to keep a 14-year-old Northern California boy incarcerated in connection with his younger sister's murder, a prosecutor told a judge that the boy once referred to the mass shooting at Sandy Hook Elementary School in Newtown, Conn., and said, "I could do something like that," reports the Calaveras Enterprise newspaper.

The assertion reportedly came Friday during a hearing to decide whether the boy, the brother of slain 8-year-old Leila Fowler, should be released pending trial. The defense had argued in a motion that the boy should be released on the grounds that new DNA evidence has surfaced that they say supports his innocence.

A judge ultimately denied the request, saying the defense merely made an assertion that new evidence shows the boy is innocent, and did not include lab reports or statements by experts that support that assertion, reports the paper.

Outside of court, defense attorney Steve Plesser disagreed, saying the judge did have access to DNA evidence that was developed by the prosecution and provided to the defense via discovery, the Enterprise reports.

The now 14-year-old suspect, who CBS News is not naming due to his young age, has been incarcerated for nearly two years in connection with the April 2013 stabbing death of his sister.

The boy, who was 12 when Leila was killed, has pleaded not guilty to juvenile charges of second-degree murder and has said an intruder came into the family's Valley Springs, Calif. home and harmed his sister before fleeing. The boy's mother, father and stepmother have said they believe he is innocent and had no motive to harm Leila.

The brutal crime sparked a manhunt for the killer that spanned days and drew the attention of the FBI. Eventually, authorities zeroed in on Leila's brother and made an arrest.

Defense attorney Steve Plesser argued Friday that his client should be freed from custody pending trial after he says an unknown male's DNA was found on a hair on the victim's body, suggesting an intruder was responsible for the crime, as the boy has always claimed. Plesser also argued there was no blood on the boy or on a kitchen knife - suggested by prosecutors to have been the murder weapon - and no evidence of the victim's blood in any drains in the home which could indicate a cleanup took place.

But, according to the Enterprise newspaper, District Attorney Barbara Yook countered by saying she believes the boy is a danger to others and referenced a time when, she says, the boy made "a threat to another child at school while holding a knife in his hand."

She said there was also another incident in which the boy made a reference to the Sandy Hook shootings and said, "I could do something like that," reports the paper.

Plesser, the defense attorney, called both of those accounts inaccurate, according to the paper. On Tuesday, the boy's other defense attorney, Mark Reichel, told 48 Hours' Crimesider his client doesn't even know what Sandy Hook is.

"During the hearing, he actually looked over and said, 'What's Sandy Hook?,'" Reichel said of the 14-year-old defendant. "That came from an informant in the jail who is crazy."

Reichel acknowledged his client did have a pocket knife but said he never threatened a schoolmate with it.

"A relative gave him a pocket knife and it fell out during gym class while he was changing," the defense attorney said.

On Friday, Yook, the district attorney, also reportedly argued that there was evidence of a "substantial cleanup" at the crime scene and that the victim's blood was found on the boy's shirt and a knife - the purported murder weapon - was found washed, on a counter.

Yook also said that the boy gave inconsistent statements in describing the alleged intruder and was unusually calm when he first spoke to a 911 dispatcher. The D.A. further stated the boy even confessed to the crime at one point, reports the Stockton Record.

Defense attorney Plesser, however, provided a different version of events and said the boy never changed his description of the alleged intruder and argued also that the boy was "sobbing" and "hysterical" on the 911 call.

In regards to the alleged confession, Plesser said the boy was interrogated multiple times without his parents and at one point, he claims the boy said, "I don't remember. I guess I did it. I don't remember... but I didn't do it."

According to the Stockton Record, Plesser characterized the statement as being invalid and said the boy in every other moment has insisted he is innocent.

"The D.A. completely mischaracterized evidence," Reichel, the boy's other defense attorney, told Crimesider.

The boy's trial is scheduled to begin May 18.