The use of public-private partnerships (PPPs) is an important development in infrastructure delivery. These contracts between a public-sector owner and a private provider bundle delivery services and provide a middle ground between traditional delivery and privatization. As of 2016, 35 states had enacted PPP-enabling laws that address such questions as the mixing of public- and private-sector funds, the treatment of unsolicited PPP proposals, and the need for prior legislative contract approval. We provide the first comprehensive empirical assessment of the laws’ impact on the utilization of private investment. We analyze the effect of a state having a PPP-enabling law and a law’s average impact. We also assess the impact of PPP-enabling-law provisions. We find that provisions that empower PPPs, such as exemptions from property taxes, exemptions from extant procurement laws, and confidentiality protections, attract private investment.

中文翻译：

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支持公共-私人伙伴关系的法律会增加对交通基础设施的私人投资吗？

公私伙伴关系（PPP）的使用是基础设施交付方面的重要发展。公共部门所有者与私人提供商之间的这些合同捆绑了交付服务，并在传统交付和私有化之间提供了中间立场。截至2016年，已有35个州颁布了支持PPP的法律，解决了公共和私人部门资金的混合，未经请求的PPP提案的处理以及事先获得立法合同批准的问题。我们对法律对私人投资利用的影响进行了首次全面的实证评估。我们分析了具有使能PPP的法律的国家的影响以及法律的平均影响。我们还评估了PPP启用法律条款的影响。我们发现赋权PPP的条款，例如免除财产税，