Top US counter-terrorism advisor John Brennan is clear about President Obama's views of CIA drone strike casualties. Civilians shouldn't be dying.

"One of the things President Obama has insisted on is that we're exceptionally precise and surgical ... if there are terrorists who are within an area where there are women and children or others, you know, we do not take such action that might put those innocent men, women and children in danger."

That's pretty clear. No dead women and kids. And the CIA has tried to oblige. Since August last year, following a spate of messy civilian deaths in Pakistan, it has apparently changed its targeting priorities so that it only hits known militants.

And if you believe 'US intelligence officials' a near-miracle has taken place. Not a single civilian death has occurred in Pakistan strikes in eleven months, despite 116 drone attacks that have killed at least 740 people. Not one.

Many beg to differ. The Bureau of Investigative Journalism, for example, with which I work, has just published a major report challenging the CIA's claims.

Working with field researchers in Waziristan, and re-examining hundreds of credible media reports, we've found dead civilians killed by drones since last August. Plenty of them, including named children.

We showed our summary findings to the US intelligence community. A senior official was robust. Our research is "wildly inaccurate". Drones are the "most precise weapon in the history of warfare." And categorically, not one civilian has died in a US drone strike in Pakistan since last August.

The CIA's drones are killing hundreds in Pakistan, most of them militants. But to do that they're blowing up mud brick houses and cars on roads. They're attacking tribal meetings, and bombing restaurants and guest houses (all recently recorded targets.)

And this 'no civilian deaths' period coincided with a steep rise in Obama's drone attacks, coupled with a collapse in co-operation between the US and its vital Pakistani intelligence allies on the ground.

The odds of civilian deaths not happening in this period seem extreme. Some very reputable news organisations (ABC, the Wall Street Journal, the BBC) have all reported civilian deaths since last August.

The mystery is not that John Brennan and others are claiming 'no civilian deaths'. The mystery is that they are not being firmly challenged given the many credible reports to the contrary.

The CIA could hedge its bets. It could say it's making every possible effort to reduce the risk to civilians, and leave room for tragic error. Instead it stands by its absolute claim of zero civilian deaths, as a counter-terrorism official confirmed to me this week.

Out in the world, there are consistent and credible reports of dead civilians, including children, killed in the strikes. Reconciling the two positions seems unlikely.

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