At a landmark TED salon last spring, economist Steven Levitt and author Malcolm Gladwell crossed swords over the real reason New York City crime dropped in the 90s. In The Tipping Point, Gladwell credited the innovative policing tactics adopted under NYC Mayor Giuliani (which focused on softer “lifestyle crimes,” like subway graffiti and zoning violations) for the reduced murder rate. At the salon — and in Freakonomics (which had just been published that week) — Levitt begged to differ. The hidden cause, he argued, was the legalization of abortion, which had prevented thousands of unwanted children from being born roughly 20 years earlier. (Levitt further argued that New York’s drop in violent crime was merely the leading edge of a nationwide trend, consistent with the timing of respective states’ abortion laws).
Who had the last word? Well that’s an open question … Nearly a year later, they’ve picked up the thread, trading persuasive posts on their respective blogs. Gladwell re-opened the discussion, Levitt and Dubner responded. And you can watch it progress from there …