We know they're counting.
But Chiarelli did not release a detailed breakdown of where and how the deaths occurred, making the claims impossible to verify.
"The number of civilians harmed by operations is an important measure of how well U.S. forces are doing in avoiding harm to civilians," the director of the Campaign for Innocent Victims in Conflict (CIVIC), Sarah Holewinski, told me. "Still, we need to see the data backing up this claim."
A US military spokesperson in Baghdad told me the statistics were "classified."
Earlier this month, Iraqi Prime Minister Nuri al-Maliki told reporters violence against civilians by occupying troops is "common" in Iraq, adding that many soldiers have "no respect for citizens, smashing civilian cars and killing on a suspicion or a hunch."
Earlier that day, U.S. soldiers at a checkpoint had shot and killed a pregnant woman on her way to give birth.
"There's a transparency problem," CIVIC's Holewinski said of the Pentagon's claims. In January, the group filed a Freedom of Information Act Request demanding access to records of families given condolences payments by the U.S. military.
CIVIC's founder Marla Ruzicka was killed by a suicide bomb in Baghdad while advocating for victims of war in Iraq. The group has long demanded that civilians killed or injured in conflict be counted and their families compensated by the governments involved.
The group successfully fought for congressional legislation requiring the U.S. government to compensate civilians killed by the U.S. military.
So-called condolences payments have been handed out since September 2003, but the military has never disclosed how many Iraqis have received money under the plan or under what circumstances the money was doled out.
"Each of those payments represents a real person who was killed," Holewinski said. "Being forthright with information lets Iraqi civilians know the U.S. in its authority position recognizes their suffering and respects those harmed in the conflict."
The only public paper trail is an audit by the Pentagon's Special Inspector General for Iraq Reconstruction. The audit of one "emergency fund" found the military provided more than $14 million to civilians in 2005 in compensation for death, injury, or property damage.
"This is a very, very minimal response," John Sloboda of IraqBodyCount.org told OneWorld. Using news reports, the Web site has documented a minimum of 38,725 civilian deaths since the war began.
Sloboda noted the Pentagon's figures don't count civilians killed in American air strikes or insurgent car bombings. "The real issue is the presence of U.S. troops in Iraq, which inflames the insurgency and causes so many civilian deaths."
The Pentagon should come clean and release all the information it has on civilian casualties in Iraq.
What are they afraid of?