When the prosecution of five Blackwater guards over the 2007 Nisoor Square massacre in Baghdad fell apart in December, it was largely blamed on the State Department's granting of immunity to guards who spoke with State officials.

Now, newly released court documents show an official at the US embassy in Iraq believed that was more than a mistake on the State Department's part. Department officials had "sought to block any serious investigation" of the massacre that took the lives of 17 Iraqi civilians, the New York Times reports.

David Farrington, a State Department security agent in the American Embassy at the time of the shooting in Baghdad’s Nisour Square, told prosecutors that some of his colleagues were handling evidence in a way they hoped would help the Blackwater guards avoid punishment for a crime that drew headlines and raised tensions between American and Iraqi officials.

The description of Mr. Farrington’s account came in closed-door testimony last October from Kenneth Kohl, the lead prosecutor in the case against the Blackwater guards.

“I talked to David Farrington, who was concerned, who expressed concern about the integrity of the work being done by his fellow officers,” Mr. Kohl recalled. He said that Mr. Farrington had said he was in meetings where diplomatic security agents said that after they had gone to the scene and picked up casings and other evidence, “They said we’ve got enough to get these guys off now.”

State Department officials led the investigation into the Sept. 16, 2007 massacre, talking to the guards immediately after the incident. But two days later, Blackwater guards gave the US officials written statements under the understanding that anything in them was immunized from prosecution, the Associated Press reports.

The Justice Department brought charges against five Blackwater guards involved in the incident. In dismissing those charges late last year, Judge Ricardo Urbina said the prosecutors had violated the defendants' rights by trying to use the immunized testimony.

US prosecutors had alleged that the guards "specifically intended to kill or seriously injure Iraqi civilians," and according to court documents alleged that one of the guards told another that he wanted to kill Iraqis as "payback for 9/11," bragging about the number of Iraqis he had shot.

The AP reports that there was a struggle among Justice Department prosecutors as to whether or not the guards' statements to the State Department could be introduced in the trial.

The case's dismissal was met with outrage in Iraq, where the government has since taken steps to ban Blackwater employees from the country.

News reports last fall suggested that Blackwater had approved bribes to Iraqi officials in an attempt to cover up the Nisoor Square massacre.

Despite all the controversy and allegations of wrongdoing, news reports indicate Blackwater will "likely" win more US government contracts, including one for the training of Afghan police.

-- With AFP