A new study says one million Iraqis have died since the start of the US-led invasion [AFP]

A recent study carried out by a UK polling firm says that more than a million Iraqi civilians have been killed due to violence since the US invasion of Iraq in 2003.

The findings, from the Opinion Research Business in association with an Iraqi research partner, contradicts a study published in the Lancet, a British medical journal, 14 months ago which put the Iraqi death toll then at approximately 655,000.

The new study says that 20 per cent of Iraqi families have lost one or more members since March 2003. This figure is said to double in and around the capital Baghdad.

However, the figures are widely at variance with other studies, which say the overall death toll is far lower.

This latest estimate has been rejected by the Iraqi government, and ignored or overlooked by the media.

Inside Story asks, how accurate is the figure likely to be? Does the foreign military presence in Iraq help maintain security, or create divisions and tensions? And who bears the ultimate responsibility for the death toll?