By David Ingram
WASHINGTON (Reuters) - The United States brought new manslaughter charges on Thursday against four former Blackwater Worldwide security guards for a 2007 shooting in Baghdad that prosecutors said killed 14 unarmed civilians.
The shooting caused tension in U.S.-Iraqi relations and raised concerns about the U.S. government's use of private contractors, who were shielded from prosecution in Iraq.
The original U.S. charges filed against the Blackwater guards in 2008 were thrown out in December 2009, about a month before a scheduled trial. A U.S. District Court judge ruled that prosecutors should have done more to exclude statements that the guards gave under threat of losing their jobs.
The case was reinstated in 2011 and prosecutors began a lengthy review of what charges they could prove in court.
The new indictment returned by a grand jury in Washington charges 33 counts, including voluntary manslaughter, attempt to commit manslaughter and using a firearm in a crime of violence.
The guards had pleaded not guilty to the nearly identical charges brought five years ago. They are Paul Slough, 34; Nicholas Slatten, 29; Evan Liberty, 31; and Dustin Heard, 32.
"We are disappointed that the Department of Justice has chosen to proceed with this prosecution, which we strongly believe has no merit whatsoever," Heard's attorney, Dave Schertler, said in a statement.
Prosecutors said the men used a sniper rifle, machine guns and grenades during the September 2007 shooting in Baghdad's Nisur Square that also wounded at least 18 people.
"The vast majority of the U.S. contractors who served in Iraq did so with honor and integrity, but, as alleged today, these defendants abused their power through a relentless attack on unarmed civilians that recklessly exceeded any possible justification," U.S. Attorney Ron Machen, the chief prosecutor in Washington, said in a statement.
A hearing in the case is scheduled for October 25. No trial date has been set, and a defense lawyer said at a hearing last month that a trial could be years away.
Prosecutors last month dropped their case against a fifth guard, Donald Ball. They said they were exercising "prosecutorial discretion" based on their "assessment of the admissible evidence against him."
Blackwater is now named Academi and is based in McLean, Virginia.
(Reporting by David Ingram; Editing by Howard Goller and Peter Cooney)