Lawyers for the teenage boy accused of slaughtering his parents and three siblings in their Fall City, Washington, home have doubled down on his claim that his younger brother committed the crimes as part of a murder-suicide.
Mark Humiston, 43, and his wife Sarah, 42, were found dead on Oct. 21 along with three of their children, Benjamin, 13, Joshua, 9 and Katheryn, 7, inside their luxury $2million lakeside mansion.
Documents obtained by DailyMail.com show the accused shooter attempted to blame the murders on Benjamin, claiming his younger sibling shot the family members and killed himself after being caught watching porn the previous evening.
Police say it was the 15-year-old who massacred nearly his entire family using his father’s Glock handgun, with his younger sister, 11 – the only survivor of the bloodbath – saying it was her eldest brother who fired two shots at her, hitting her in the neck and arm.
The teen’s attorneys insist his murder-suicide theory is ‘forensically viable,’ according to court documents obtained by The Seattle Times.
Lawyers for the 15-year-old boy (pictured) accused of killing his parents and three siblings in Fall City, Washington, claim his brother committed the crime
The unnamed teenager is accused of massacring all but one of his family members with his father’s Glock handgun at their luxury $1.4million home in the leafy town 30 miles from Seattle
Defense attorney Amy Parker wrote in a court declaration on November 1 that there are ‘two versions of events.’
‘No one who was involved in this shooting would have escaped without a substantial amount of blood [on them],’ she wrote, arguing there is no mention the boy had blood on him in 106 pages of evidence.
‘Because of the quick arrest in this case and the narrow focus by law enforcement, a defense review of the crime scene is needed.’
Parker said that defense attorneys were only allowed into the crime scene for an hour several days after the killings, and they requested more time to investigate the house.
‘It is my experience that law enforcement can and does engage in bias investigations when they think they have the “right” suspect,’ Parker said.
According to detectives, the 15-year-old also attempted to stage the crime scene to lend credence to his story that it had been a murder-suicide perpetrated by Benjamin.
Electrical engineer Mark Humiston, 43, and his registered nurse wife Sarah, 42, were found dead at the home along with three of their children
The teens three siblings, Benjamin, 13, Joshua, 9 and Katheryn, 7, were killed in the shooting. His 11-year-old sister survived
The couple were extremely religious – imposing a highly-controlled existence on their five kids which included dictating who they could be friends with and homeschooling them
The report noted that a black Glock pistol had been placed in the child’s hand but forensic investigators spotted that the weapon hadn’t been fired and that blood splatter from a fatal wound to the boy’s face was in the wrong place.
The surviving 11-year-old girl told police that the gun used to commit the monstrous killings was her father’s silver Glock handgun, which he kept in a small lockbox by the front door, Fox News reported.
She also noted that out of all of her siblings, her oldest brother was the only one who knew the combination to access the firearm.
The 11-year-old sole surviving daughter played dead before she escaped the bloodbath through a ‘fire window’ in her room and ran about a quarter of a mile away to a neighbor’s house.
In a disturbing detail, she remembered her brother leaning over the three family members he gunned down in the hallway before touching their bloodied bodies to make sure they were actually dead.
Defense attorneys said they were only allowed into the crime scene for an hour several days after the killings, and requested more time to investigate the house
Her older brother then re-entered her bedroom, where she closed her eyes and held her breath as he stood next to her bed.
Once her brother left her room and she could hear him upstairs on the phone, she used the window to escape before running to her neighbor’s house and incessantly ringing the doorbell – fearing her brother would come to find her.
The surviving daughter, who was bleeding from her neck and hand, told the neighbors that her family was dead at the hands of her own brother before they phoned police.