This introduction provides an overview to the special issue, which marks the twentieth anniversary of the shootings at Columbine High School by considering the effect on policy addressing school violence and mass shootings. We asked each of the contributors to consider changes in their area of interest over the past two decades as well as future research and policy issues. The resulting five contributions take various forms: three are traditional scholarly articles, one is a personal commentary, and one is an afterword that combines a scholarly format with professional reflection. In our introduction, we summarize each one. As each article identifies the need for continued work in this area, and we conclude by providing a few examples of this research.

中文翻译：

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特刊简介：哥伦拜恩的遗产——20 年后对政策的影响

本介绍概述了特刊，该特刊通过考虑对解决校园暴力和大规模枪击事件的政策的影响来纪念哥伦拜恩高中枪击事件 20 周年。我们要求每位贡献者考虑过去二十年他们感兴趣的领域的变化以及未来的研究和政策问题。由此产生的五篇贡献形式多样：三篇是传统的学术文章，一篇是个人评论，一篇是将学术形式与专业反思相结合的后记。在我们的介绍中，我们总结了每一个。由于每篇文章都确定了在该领域继续开展工作的必要性，因此我们通过提供此研究的一些示例来总结。