The car was Korean-made. A Kia. Coloured red. Jimmy Massey saw it from his checkpoint near Baghdad stadium.
"It did not heed our warning signs and we discharged our weapons," recalls the former US platoon sergeant.
"The driver wasn't hit but the three occupants were hit and expiring fast. When we pulled them out we didn't find any weapons or explosives, and the driver asked me why did we shoot them. 'We aren't terrorists,' he said. It was at that point I realised what we were doing was violating international law as well as the Geneva conventions."
Massey (34), who is in Dublin this week to speak about his experiences in Iraq, talks in short, measured sentences - a reflection of the discipline instilled in him during his 12 years in the Marines.
The incident with the Kia took place just days before his colleagues helped to pull down Saddam Hussein's statue in Firdos Square. While his senior officers celebrated "the fall of Baghdad", he began to question them about US intentions in Iraq.
"I felt I was going into Iraq to liberate the people, and find weapons of mass destruction. But when I got to Baghdad the entire mission changed. The intelligence reports painted the average Iraqi as a terrorist and gave us a carte blanche to shoot first and ask questions later."
The North Carolina man, whose rank put him in charge of more than 45 machine-gunners, snipers and other infantrymen, said he had "lit up" on civilians, and was "just as guilty as the other Marines".
"Over three months, we killed 30-plus civilians at these checkpoints. After every casualty there was an escalation of violence."
A combination of "my conscience and knowing I was breaking international law" prompted him to challenge his lieutenant over killing of civilians. The Marine Corps conducted an investigation into the stadium shooting - without interviewing Massey - and cleared all those involved of wrongdoing.
Now marked as a trouble-maker, he believes he would have been jailed had he not got a lawyer to represent him. In December 2003, he was discharged from the Marines with post-traumatic stress disorder.
He has since written a book - released this month by a French publishing house. As well as detailing his experiences in Iraq, it criticises the US policy of using healthcare and other economic benefits as bait to conscript financially-deprived youths. Massey joined the Marines because he couldn't afford to continue paying his engineering college fees.
"As I look at it, the taxpayers paid my salary while I was in the Marine Corps, and ultimately my responsibility stays with the taxpayers. They should know they are funding bullets that are being put into innocent Iraqis."
Massey will speak at a public meeting tomorrow at 7.30pm in TCD. His book Kill! Kill! Kill! is published by Éditions du Panama.
