Blackwater destroyed shooting evidence

The evidence gaps will force investigators to rely more heavily on testimony and other statements from witnesses. But even those efforts have been hampered by a State Department deal that gave Blackwater guards limited immunity for their statements following the incident. As a result, the Justice Department cannot use those interviews in its criminal investigation.

There were 19 security guards at the scene. Investigators believe only a few fired their weapons. Investigators are pushing ahead with the search for additional evidence and so far are focusing on as many four guards who could face criminal charges.

Over the past two months, prosecutors have brought several guards before a Washington grand jury to describe their recollection of the shooting. According to the initial State Department report, the shooting occurred as the Blackwater convoy was responding to a car bombing about a mile outside the U.S.-protected Green Zone, which houses the Iraqi government and several embassies.

James Sweeney, a lawyer representing several guards, would not discuss the forensic gaps or whether the grand jury investigation is helping authorities bridge them. He said Blackwater guards are patriots, not aggressors.

"They are good, solid intelligent Americans. They're good people," Sweeney said. "They're protecting U.S. diplomats."

North Carolina-based Blackwater is the largest private security company protecting U.S. officials in Iraq. It has been paid more than $1 billion from federal contracts since 2001. Despite criticism, Blackwater notes that no official under its protection has been killed or seriously injured.

Blackwater also strongly denies wrongdoing in a weapons smuggling investigation by federal officials in North Carolina. Two former employees, who prosecutors say are aiding the investigation, were sentenced to probation Thursday on gunrunning charges.

Blackwater and other contractors operate in a legal gray area. They are immune from prosecution in Iraqi courts. If the Justice Department wants to bring criminal charges such as assault, manslaughter or murder in a U.S. court, prosecutors would have to do so under the Military Extraterritorial Jurisdiction Act.

That would require the government to show that State Department contractors were "supporting the mission of the Department of Defense overseas." Defense lawyers are expected to argue that guarding diplomats was a purely State Department function, one independent from the Pentagon.

The Justice Department has said it could be some time before it decides whether it will bring charges in the case.

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