The Pentagon says its rules of engagement haven't changed, despite them being 'adjusted' last month

The Pentagon is disputing reports that its rules of engagement in Iraq have been loosened following a deadly strike in Mosul that killed more than 100 civilians.

But its own spokesman seemed to confirm last month it did exactly that.

Previously, American advisors on the ground were required to go through an approval process with a command center in Baghdad before strikes were carried out. But in February, the AP reported the military had dropped this requirement to speed up strikes, with some advisors operating on the ground being "empowered" and no longer required to coordinate with Baghdad.

From the AP:

The spokesman for the U.S.-led coalition, Air Force Col. John Dorrian, confirmed to The Associated Press the rules of engagement in the fight against IS in Iraq were adjusted by the December directive, explaining that some coalition troops were given the "ability to call in airstrikes without going through a strike cell."

More coalition forces have been "empowered" to have the ability to call in strikes in the Mosul operation, Col. Dorrian told a Pentagon press briefing on Wednesday.

Now contrast that with reporting from The New York Times, in which spokesman Capt. Jeff Davis said rules had not been loosened. Besides its easing of the process, advisors were embedded at lower echelons of Iraqi security forces at the brigade and battalion level, rather than division - meaning that US forces have increasingly gotten closer to direct combat.

Davis told The Times the strike that killed hundreds in Mosul was "at the request of Iraqi security forces," and did not mention American advisors. This seems to suggest that US military planners may have received a direct request for air support from Iraqi troops, which may not have attempted to minimize collateral damage.

The idea of putting Iraqi troops in the driver seat with the ability to call in American air strikes seems a result of the "adjustment" of rules the AP had reported. In that story, published on Feb. 24, an Iraqi Army general is able to call an American lieutenant colonel to report a mortar attack and request support directly, something that had not been possible last year. 

Col. Dorrian did not immediately respond to a request for comment.

The Pentagon may be technically accurate when it says rules of engagement have not changed. Rules of engagement guidelines help troops understand when they can and cannot fire at an opposing force. Typically, troops are required to get positive identification of a target, only fire when under threat, and are required to minimize collateral damage when calling in air strikes.

While the overarching guidelines may not have changed, the process for carrying out air strikes certainly has - and it may be the reason why Mosul could be the site of the largest loss of civilian life since the start of the Iraq war in 2003. 

The Pentagon acknowledged on Friday that it would investigate the March 17 strike, according to The New York Times. The process is expected to take at least a few weeks.

"Coalition forces comply with the Law of Armed Conflict and take all reasonable precautions during the planning and execution of airstrikes to reduce the risk of harm to civilians," a release on the coalition website says.