NEW YORK -- Adam Lanza, whose shooting rampage at the Sandy Hook Elementary School left 20 first-graders and six adults dead, acted with deliberation despite his mental health problems and is criminally responsible for the attack that horrified the nation, investigators said Monday.
In a 48-page report, the state's attorney for Connecticut's Danbury region, Stephen J. Sedensky III, said investigators could not establish a conclusive motive for the attack or why Lanza chose Sandy Hook Elementary School in Newtown, Conn., as the target for the shooting other than it was close to his home.
Lanza started his rampage by killing his mother and ended it by committing suicide Dec. 14, 2012. The report comes almost a year after the tragedy, which prompted a push for new federal gun control legislation that stalled in Washington. Although national efforts have faltered, some states, including Connecticut, toughened their laws.
The eagerly awaited report gives the clearest picture yet of the events in one of the nation's deadliest mass shootings.
Lanza "had significant mental health issues that while not affecting the criminality of the shooter's mental state for the crimes or his criminal responsibility for them, did affect his ability to live a normal life," the report states. It goes on to say that Lanza did not help himself deal with his mental issues.
"In 2005, the shooter was diagnosed with Asperger's disorder and was described as presenting with significant social impairments and extreme anxiety," the report says. Lanza "refused to take suggested medication and did not engage in suggested behavior therapies."
Investigators also said they found no evidence to suggest that Lanza had taken any medication that would affect his behavior or by any means explain his actions.
Lanza started the day at home, where he shot and killed his mother, Nancy, in her bed. He used a .22-caliber gun to shoot her at close range and the weapon was recovered at her bedside.
He then went to the school armed with 30-round magazines for a Bushmaster .223-caliber rifle, along with several other weapons, and blasted his way through the glass front entrance. In less than five minutes, Lanza fired 154 rounds from the long gun, killing the children and six educators. He committed suicide by shooting himself with his handgun.
Investigators acknowledged Lanza's mental illness but said it did not excuse his actions. Lanza committed crimes including murder and attempted murder with special circumstances as well as assault. His condition would not have been a viable defense, investigators said.
His mental state "is no defense to his conduct as the evidence shows he knew his conduct to be against the law. He had the ability to control his behavior to obtain the results he wanted, including his own death." "Did he have a motive to do what he did?" the report asks of Lanza's actions. "This investigation, with the substantial information available, does not establish a conclusive motive."
Investigators did find strange behavior to justify questions about Lanza's mental health.
In November 2012, Nancy Lanza sought to buy the shooter another computer or parts for a computer for him to build. She was concerned about him and said that he hadn't gone anywhere in three months and would communicate with her by email only, though they were living in the same house. At one point, Nancy Lanza also had plans to sell her home in Newtown and move to either Washington state or North Carolina, according to the report. She reportedly had told the shooter of this plan, and he apparently stated that he wanted to move to Washington. The intention was for the shooter to go to a special school in Washington or get a computer job in North Carolina, according to the report.
The investigation praises police who responded "within minutes of the first shots being fired." It also praises the school staff for heroic actions to protect the children. "The combination saved many children's lives," investigators said.
"The report is a gripping, graphic reminder of the cruelty and brutality that caused this unspeakable tragedy, and a testament to the bravery and courage of scores of first responders," Sen. Richard Blumenthal (D-Conn.) said in a prepared statement.
"The lessons of this report are simple: We must improve school security, increase mental health services, and require background checks for all gun purchases so we can keep firearms out of the hands of dangerous people. We should not wait for another gun violence tragedy to institute these reforms and other common sense measures. The cost of inaction is too great."
As the massacre anniversary approaches, the town is bracing for a very difficult period. Plans called for taking down the school building in time for the anniversary.
The family of at least one Sandy Hook victim, teacher Victoria Soto, criticized the decision to release the details. "As we close in on the end of a very difficult year, the releasing of this report is yet another blow that our family has been dealt," the family said in a statement. "So yes, we have read the report; no, we cannot make sense of why it happened, we don't know if anyone ever will."