Hugh McQuaid file photo

(Updated 6:15 p.m.) State police released thousands of pages of redacted reports Friday afternoon on their investigation of the Sandy Hook shooting. While the documents do not provide a motive for the murders, they do shed some light on the 20-year-old gunman.

The state police report comes more than a year after 20 year-old gunman Adam Lanza murdered 20 school children and six educators at Sandy Hook Elementary School in Newtown. Lanza also murdered his mother Nancy at their Newtown home and took his own life as police responded to the shooting at the school.

In a cover letter to the documents posted Friday on the Emergency Services and Public Protection Department website, Commissioner Reuben Bradford praised the heroism displayed the school staff and emergency responders on the day of the shooting.

“In the midst of the darkness of that day, we also saw remarkable heroism and glimpses of grace,” he wrote.

Bradford said the investigation of the shooting took tens of thousands of law enforcement hours and has been unprecedented in Connecticut State Police history. He said the investigation is now closed but the agency anticipates that supplemental reports will be added to the file in the coming months.

State police personnel redacted a large amount of information from the documents. Names and identifying information of children was withheld.

Similar information was redacted pertaining to most witnesses. Bradford said many of the individuals who have been publicly associated with incident have been harassed or intimidated. He said the agency exercised a “permissive exemption” to disclosure laws to withhold the names of witnesses whose identities are not already known.

“Balancing the often-competing interests of government transparency and individual privacy has been difficult,” he wrote. “I believe that the redacted report that is being released includes as much detail as possible while protecting confidential information and without unduly infringing on the privacy rights of those whose lives have been so profoundly impacted through no fault of their own.”

Bradford said he hoped the report would provide information useful to preventing future tragedies while allowing those affected by the incident to continue their personal healing processes.

A commission appointed by Gov. Dannel P. Malloy was split on whether Danbury State’s Attorney Stephen Sedensky’s 43-page report released at the end of November provided enough information about Lanza’s mental state.

At its meeting a week ago, Harold Schwartz, a psychiatrist and member of the Sandy Hook Advisory Commission, wanted to know more about the shooter from his father. Schwartz suggested that the commission reach out to Peter Lanza to ask him if he could provide more insight into his son’s mental state.

According to the documents released Friday, the police already interviewed Mr. Lanza.

A few days after the shooting, a state trooper and an Alcohol Tobacco and Firearms agent interviewed Mr. Lanza and his lawyer at a law office in Stamford. Lanza told the law enforcement officers that he rarely saw Adam and although he tried communicating with his son through email, his son stopped responding in 2010.

Although much of the interview focused on how Adam Lanza came to have access to guns, the trooper asked the father to help him understand more about Adam and what would cause him to carry out the horrific shooting.

“Peter stated that Adam had Aspergers Syndrome, but that he clearly had some other medical condition in order to carry out the events at Sandy Hook Elementary School,” a state trooper wrote in a report.

According to Mr. Lanza, his son “loved being a kid” and was very happy when he was around eight or nine years old. He said his son enjoyed his time at Sandy Hook Elementary School. But he noticed a change in Adam’s demeanor between 11 and 12 years old.

“He noted that Adam seemed less happy, stressed and frustrated, but did not exhibit any outward signs of anger or aggression,” the report said. “Peter stated that Adam hated being photographed or seen in any pictures.”

In October 2006, Adam Lanza was taken to the Yale Child Studies Center where he was evaluated by Dr. Robert King and later by Advanced Practice Registered Nurse Kathleen Koenig, who met with the youth four times through February 2007.

He was diagnosed with “profound Autism Spectrum Disorder, with a secondary diagnosis of Obsessive Compulsive Disorder.” Koenig prescribed Celexa, an anti-depressant/anti-anxiety medication and follow-up visits, but Nancy Lanza told Koenig her son was “unable to raise his arm” after taking the medication.

“Nancy Lanza stated due to her son’s symptoms, he would be discontinuing the use of the medication,” according to the interview Koenig gave police.

Mr. Lanza also told police his son had Obsessive Compulsive Disorder. He said Adam was home schooled after his freshman year at Newtown High School, according to the report.

“Peter stated that Adam viewed his home as a comfort zone where school and social interaction led to pressure,” the report said.

Police interviewed another witness, whose identity was redacted but seemed to have a close relationship with Nancy Lanza. The witness said he had never met Adam, but had spoken to Nancy about him. The witness said Nancy never told him of any times when Adam was violent with her, but he got the feeling she “did a lot for Adam to assure that he was happy and appeased.”

This witness said Nancy Lanza had planned to sell the home they shared and to move to the state of Washington or North Carolina.

“Further, [redacted] related that Nancy knew that she was not going to be able to effectively show / sell her home while Adam was living within. Her plan was to purchase an RV to facilitate their move . . . During their trip [redacted] related that Nancy would then sleep in a motel / hotel and Adam would sleep in the RV as he would not sleep in a motel,” the report read.

According to the witness, Nancy wanted to move to Washington, where there was a special school Adam wanted to attend, or North Carolina, where a family friend had agreed to teach Adam to work at a computer technology business he owned.