Crime and the economy

This article by Heather MacDonald from the Wall Street Journal rises an interesting question for the law and economics types: If poverty is the root cause of lawlessness, why did crime rates fall when joblessness increased? MacDonald writes,

The recession of 2008-09 has undercut one of the most destructive social theories that came out of the 1960s: the idea that the root cause of crime lies in income inequality and social injustice. As the economy started shedding jobs in 2008, criminologists and pundits predicted that crime would shoot up, since poverty, as the "root causes" theory holds, begets criminals. Instead, the opposite happened. Over seven million lost jobs later, crime has plummeted to its lowest level since the early 1960s. The consequences of this drop for how we think about social order are significant.