Washington (CNN) -- A report made public Thursday on events surrounding the deadly shooting spree at Fort Hood, Texas, in 2009 provides new details on the failure of anti-terrorism officials to act on e-mail traffic between Maj. Nidal Hasan and major terrorist figure Anwar al-Awlaki.
The 173-page report by William Webster, a former FBI and CIA director, describes FBI policies and procedures that failed to prevent the shooting spree. Hasan is charged with 13 counts of premeditated murder and 32 counts of attempted premeditated murder.
The FBI and Defense Department were stunned by the shootings, and FBI Director Robert Mueller ordered a detailed review by the Webster commission, which Mueller appointed.
According to the commission's report, in a May 31, 2009, e-mail from Hasan to al-Awlaki's website, Hasan discussed his views on suicide bombings.
"I would assume that a suicide bomber whose aim is to kill enemy soldiers or their helpers but also kill innocents in the process is acceptable." Less than six months later, officials say, Hasan jumped on a desk at Fort Hood, armed with two pistols, and began firing as he yelled "Allahu Akbar," Arabic for "God is great."
There were 18 e-mail messages between Hasan and al-Awlaki between December 2008 and June 2009, the report said. A Joint Terrorism Task Force in San Diego that was investigating al-Awlaki passed two of the messages on to another task force in the Washington, D.C., area, where Hasan was living.
The report said the e-mails between Hasan and al-Awlaki should have been passed by the FBI in the Washington Field Office to the Defense Department bosses for whom Hasan worked. But the FBI saw no evidence of terrorist activities in his case, and believed the information in the e-mails was too sensitive to share because visiting extremist websites is not grounds for taking action.
The report also said there was no clear system in place to determine which office would follow up on a particular lead and to make sure leads would be followed in a timely manner.
In a statement Thursday, the FBI acknowledged "shortcomings in FBI policy guidance, technology, information review protocols and training." The FBI said it had reviewed 18 recommendations in the report and "has already taken action to implement them."
Sen. Joe Lieberman, I-Connecticut, said the report confirms many of the findings of his committee's earlier review.
He said he is pleased "for the first time the report declassifies the communications between Hasan and Anwar al-Awlaki so that all Ameriicans, especially the families of the victims, can understand Hasan's radicalization and the full scale of the tragedy for which he is responsible."
Lieberman added, "We are concerned that the report fails to address the specific cause for the Fort Hood attack, which is violent Islamist extremism"
Hasan is scheduled to be tried in a military court in Texas. Al-Awlaki was killed in a targeted U.S. drone attack in Yemen last year.