Western Connecticut State University, File, Associated Press
HARTFORD, Conn. — A yearlong investigation into the Newtown school shooting has provided disturbing insights into the gunman who killed his mother and then massacred 26 other people, but it still has not provided a motive.
Prosecutors closed the case Monday on the Sandy Hook Elementary shooting last December. Their report offered a chilling portrait of 20-year-old Adam Lanza as a loner who was obsessed with violence and bound by ritualistic behavior.
But they were unable to answer the question that everyone has been asking since the tragedy: Why?
"The obvious question that remains is: 'Why did the shooter murder 27 people, including 20 children?' Unfortunately, that question may never be answered conclusively," the report said.
To try to figure out the motive, investigators said, they interviewed members of Lanza's family — his father and brother cooperated fully — along with teachers and others. They said they also tried within the limits of privacy laws to gather information on his medical treatment.
They found no evidence he had taken any medication that would have affected his behavior or explain the bloodbath.
Lanza "was under no extreme emotional disturbance for which there was a reasonable explanation or excuse," the report concluded.
It said that in fifth grade, Lanza wrote a book that included tales of children being slaughtered and a son shooting his mother in the head.
In the years that followed, he was obsessed with mass murders, assembling articles, photos, books, footage and violent video games, including one in which players gun down students in school. He even kept a spreadsheet ranking mass murders.
The summary released by the lead investigator, State's Attorney Stephen Sedensky III, describes Lanza as having "significant mental health issues" but sure knowledge of what he was planning: Besides having the spreadsheet, he smashed his computer hard drive and used earplugs during the shooting.
Lanza killed 20 first-graders and six educators with a semi-automatic rifle at the school on Dec. 14. He also shot his mother in the forehead inside their home. He committed suicide with a handgun as police arrived at the school.
Sedensky said there was no clear indication why Lanza chose Sandy Hook Elementary other than that it was close to his home. He attended Sandy Hook from first through fifth grade, but he was never assigned to the classrooms where the shootings took place.
The spiral-bound manuscript that Lanza wrote in the fifth grade, "The Big Book of Granny," was among items seized from his home. There is no indication he ever handed in the book at school.
The main character has a gun in her cane and shoots people, and another character likes hurting people, especially children.
Lanza also became obsessed with the 1999 Columbine High shootings and other such mass killings, the report said.
The guns he used in the attack had been purchased legally by his mother, who often took her son shooting and, according to the report, had written out a check to buy him a pistol for Christmas. Their house also contained knives, swords, spears and other sharp weapons.
The report said that in 2005, Lanza was diagnosed with Asperger's disorder — an autism-like condition that is not associated with violence — and that he lacked empathy for others and behaved strangely. He seemed to have few friends.
Nobody was allowed into his bedroom, not even to clean, according to the report. The windows of the room were covered with black trash bags. The report also said Lanza also disliked birthdays, Christmas and holidays and did not like to have his hair cut.
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