Miles Kimball catches Bret Stephens pulling a fast one on Wall Street Journal readers – but it’s much worse than Kimball says.

Kimball take Stephens to task for overstating the economic progress of poorer Americans by presenting nominal figures, without any adjustment for inflation. What Kimball doesn’t mention is that the constant-dollar figures are presented by the Census in the same table (Excel file) from which Stephens is taking his numbers – and the constant-dollar figures actually show a small decline in the incomes of the bottom 20 percent.

Wait, it gets worse. In the same piece in which he commits the unforgivable sin of using nominal incomes as a measure of progress, Stephens also accuses President Obama of a “factual error” in claiming that the top 10 percent receive half the income; it’s the top 20 percent, says Stephens, and there has been no significant rise since the mid-1990s.

What’s going on here? Stephens is citing the Census data, which everyone who knows anything about inequality knows has a problem with very high incomes thanks to “top-coding”. The Piketty-Saez data, which use tax returns to estimate income shares, do indeed show the top 10 percent receiving half the income, up from 42 percent in 1995. Maybe you don’t like those estimates, but Obama made no mistake – while Stephens did.

Why doesn’t this sharp rise show in the Census data? Because almost all of it took place among the top 1 percent – the income range that the Census data, which are survey-based, can’t effectively track.

OK, we’re still not done here. Stephens then goes on to suggest not just that there has been no rise in inequality since 1995, but that not much has changed since 1979. So let me pull out the Congressional Budget Office – they’re right behind this sign over here – to comment on that:

CBO finds that, between 1979 and 2007, income grew by:

•275 percent for the top 1 percent of households,

•65 percent for the next 19 percent,

•Just under 40 percent for the next 60 percent, and

•18 percent for the bottom 20 percent.

The point here, as on so many other economic issues, is that we are not having anything resembling a good-faith debate.

We could have a debate about whether rising inequality is a problem, and whether measures intended to curb it would do more harm than good. But we can’t have that kind of debate if the anti-populist side won’t acknowledge basic facts – and it won’t. In his piece Stephens trashes Obama, accusing him of making a factual error when he did no such thing; then proceeds to commit just about every statistical sin you can imagine in an attempt to minimize the rise in inequality. In the process he leaves his readers more ignorant than they were before. When this is what passes for argument, how can we have any kind of rational discussion?

Oh, and just FYI: this is the kind of journalism that the great and the good deem worthy of a Pulitzer Prize.