The numbers being bandied about on casualties in Iraq are highly controversial. Here's one reason why some are skeptical of the looming report by general Petraeus:

When Petraeus told an Australian newspaper last week that sectarian attacks had decreased 75 percent "since last year," the statistic was quickly e-mailed to U.S. journalists in a White House fact sheet. Asked for detail, MNF-I said that "last year" referred to December 2006, when attacks spiked to more than 1,600.

By March, however - before U.S. troop strength was increased under Bush's strategy - the number had dropped to 600, only slightly less than in the same month last year. That is about where it has remained in 2007, with what MNF-I said was a slight increase in April and May "but trending back down in June-July."

Petraeus's spokesman, Col. Steven A. Boylan, said he was certain that Petraeus had made a comparison with December in the interview with the Australian paper, which did not publish a direct Petraeus quote. No qualifier appeared in the White House fact sheet.

The deeper problem is that the commander-in-chief is un-trustworthy. We know he is uninterested in empirical reality, just spinning whatever reality suits him politically. If Petraeus decides to join this partisan spin, his own reputation will suffer. Let us have data - real, unvarnished, hard data. We won't get that from Bush or Cheney. They have done nothing but lie and spin about the war for four years. Maybe Petraeus can surprise us. But my bullshit detector is on high alert.

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