Neutralizing the tentacles of organized crime. Assessment of the impact of an anti-crime measure on mafia violence in Italy
研究意大利1991年法令规定的市议会因黑手党影响而解散的措施，在2010-2019年间是否减少了针对政治人物的暴力，发现该措施有效且效果持续至少七年。
Organized crime tightens its corrupting influence on politics through violent intimidation. Anti-crime measures that increase the cost of corruption but not of the exercise of violence might, on the one hand, lead mafia-style organizations to retaliate by resorting to violence in lieu of bribery. On the other hand, this kind of anti-crime measure might also induce criminal clans to go inactive, owing to the lower expected payoff from the “business” of influencing politics, which would reduce violence. To determine which of these possible effects is prevalent, we undertake an empirical assessment of the impact of city council dissolution for mafia influence in Italy as prescribed by Decree Law 164/1991 in discouraging violence against politicians in the period 2010–2019. The difference-in-differences analysis shows that in the dissolved municipalities the enforcement of the Law reduces violence and that the effect persists (at least) for seven years after the compulsory administration. The most likely driving channel of this result is the renewed pool of politicians elected after compulsory administration.