Passage Summary: Dapolito claims that because rent control has been shown to ruin the quality and availability of apartments, the city council must not have intended to protect those things when they passed the law.

Conclusion: The city council's actual goal is not to maintain the quality or availability of local rental housing.

Reasoning: A study of fifteen communities demonstrates that rent control actually leads to higher prices and lower quality and availability of housing.

Analysis: This argument relies on a massive logical gap between the effect of a policy and the intent of the policymakers. Dapolito assumes that if a policy fails to achieve a goal, then that goal must not have been the intended one. To make this 'Sufficient,' we need an assumption that bridges this gap, such as 'if a person's actions result in X, then that person did not intend to achieve the opposite of X.' It’s a cynical take on politics, assuming that no one ever makes a well-intentioned mistake.