"If econometric studies were all there were to the story of lead, you'd be justified in remaining skeptical no matter how good the statistics look. Even when researchers do their best—controlling for economic growth, welfare payments, race, income, education level, and everything else they can think of—it's always possible that something they haven't thought of is still lurking in the background. But there's another reason to take the lead hypothesis seriously, and it might be the most compelling one of all: Neurological research is demonstrating that lead's effects are even more appalling, more permanent, and appear at far lower levels than we ever thought."
And the rest of the second page goes into much more detail.
In other words, just saying "correlation doesn't imply causation" doesn't win you the thread. There is clear causation evidence at the neurological level.
No, we don't see causation at the neurological level. The "correlation ≠ causation" meme doesn't just undermine overspeculative econometric conclusions: it undermines overspeculative biological conclusions too. The article may show correlations at the econometric level (I'm not convinced). It reports correlations at the medical level. But correlation still ≠ causation, and so it's not clear that lead causes crime "neurologically". Indeed it's not clear that any single factor trumps the human element in committing crime. At some level, crime is always a human choice. That's why we call it "crime." The overall fallacy of the article, therefore, is that statistical analysis—with its weak ability to establish causation—can shed more light on crime than human factors can, when crime is clearly a highly complex, volitional, and "human" behavior that resists analysis of any kind.
The first paragraph of that second page reads:
"If econometric studies were all there were to the story of lead, you'd be justified in remaining skeptical no matter how good the statistics look. Even when researchers do their best—controlling for economic growth, welfare payments, race, income, education level, and everything else they can think of—it's always possible that something they haven't thought of is still lurking in the background. But there's another reason to take the lead hypothesis seriously, and it might be the most compelling one of all: Neurological research is demonstrating that lead's effects are even more appalling, more permanent, and appear at far lower levels than we ever thought."
And the rest of the second page goes into much more detail.
In other words, just saying "correlation doesn't imply causation" doesn't win you the thread. There is clear causation evidence at the neurological level.