Matt Apuzzo / The New York Times – 2014-07-21 00:38:25

WASHINGTON (July15, 2014) — As a line of Blackwater armored trucks pushed through heavy traffic away from the smoking wreckage of Nisour Square in Baghdad one day in 2007, a turret gunner waved his arms, telling nearby Iraqis to get down. He was warning them about the threat of his own American convoy.

“At this point, my teammate’s been firing wildly, and I don’t want these kids to get shot,” the gunner, Matthew Murphy, recalled recently. “And I don’t want anybody else to get shot.”

For years, Iraqis have described running for cover, praying and watching family members die in the Nisour Square shooting. Now, in court testimony that continues this week, former Blackwater employees have offered the first public accounts of what it was like inside the security company’s trucks that day.

In a courtroom at a federal courthouse here, the men confronted their onetime colleagues standing trial for a shooting that left 17 Iraqis dead. Their testimony recalled images from the Iraq war’s nadir, when Blackwater’s highly paid contractors guarded American diplomats as they tried to forge a lasting peace.

Almost immediately, the Nisour Square shootings shattered the camaraderie of the team, men who had shared lousy food and tight quarters, who had trusted one another with their lives each day and played video games and poker together at night. Each defendant stood, expressionless, as a former colleague, Adam Frost, identified them in court on Monday.

“We’ve been in firefights before,” said Mr. Frost, a former Army Special Forces member and Blackwater contractor. “This one just felt different.”

It unfolded on Sept. 16, 2007, after a car bomb exploded. As one Blackwater team raced back to the safety of the Green Zone, a second convoy known as Raven 23 moved into Nisour Square to stop traffic and provide the first team a path. The shooting began soon after the Raven 23 trucks arrived. Prosecutors say Blackwater fired unprovoked.

“I saw people huddled down in their cars, trying to shield their children with their bodies,” Mr. Frost said Monday.

On Tuesday, a third Blackwater guard, Mark Mealy, identified several of his former colleagues who he said had fired. He said one teammate — he could not say who — shot an unarmed Iraqi who was holding up his hands. “And he just fell straight backward,” Mr. Mealy said.

The contractors standing trial said they were caught in a firefight and feared for their safety. They said the team leader called out, “Contact, contact,” over the radio, indicating combat with an enemy. Another colleague radioed that an Iraqi police officer was shooting at the convoy, Mr. Frost testified.

When Mr. Murphy testified this month, prosecutors asked time and again whether he had seen a danger that warranted a Blackwater attack with machine guns and grenades.

“Did he appear to be a threat to you?”

“Did you see any threats to the Raven 23 convoy?”

“Did you see any men with AK-47s around that area?”

“Do you see any armed men at all?”

Each time, Mr. Murphy said no.

Over all, however, the Blackwater testimony provided mixed results for prosecutors. Mr. Murphy said he heard AK-47 gunfire, though he never saw anyone firing on the convoy. Mr. Frost said he was certain the convoy was under fire. And he said his teammates responded appropriately to the day’s first target, a white sedan, which he said could have contained a bomb.

Defense lawyers say the Blackwater guards were on edge during one of the war’s most dangerous periods. Through cross-examination of Mr. Murphy and Mr. Frost, the lawyers conveyed the war’s terror. Both men spoke of seeing possible danger everywhere. Mr. Frost recalled Iraqis — civilians and police officers alike — plotting against Americans. He told jurors that, when he arrived in Iraq with the Army in 2003, Iraqis greeted and cheered.

“We were like celebrities; everybody loved us,” he said. “I went back in 2007, and everybody hated us.”

The Blackwater guards standing trial are Dustin L. Heard, Evan S. Liberty, Nicholas A. Slatten and Paul A. Slough. All face manslaughter charges except Mr. Slatten, who was charged with murder after prosecutors missed a deadline and let the statute of limitations for manslaughter expire.

A fifth guard, Jeremy P. Ridgeway, has pleaded guilty to manslaughter and is expected to testify later. Much of the most damning testimony so far has been directed toward Mr. Ridgeway, and in a case with witnesses disagreeing over who shot whom, defense lawyers are eager to portray him as Blackwater’s villain.

Mr. Murphy said he was furious when the convoy returned to the Green Zone. “I’ve seen people completely unarmed, people doing nothing wrong, get shot,” he said. He called it “the most horrible, botched thing I’ve ever seen in my life.”

Mr. Frost said he knew immediately that the shooting would erupt into an international episode. He and a few others met the next day and shared concerns about what had happened. Soon, Mr. Frost said, he began to get dirty looks and nasty comments from colleagues.

The team leader, Mr. Frost said, did not share the concerns. “He basically said, if we had problems with what happened out there, maybe we were the ones with the problem,” Mr. Frost recalled. “And maybe we needed to find new lines of work.”

The divisiveness did not last long. “They fired me,” he said.

A version of this article appears in print on July 16, 2014, on page A15 of the New York edition with the headline: Witnesses Testify Against Ex-Blackwater Colleagues in Case of 2007 Iraq Killings.

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