1964年“《纽约时报》诉沙利文案”判决后，美国的诽谤法由传统的普通法性质转入“诽谤法的宪法化”，该案确立的“公众人物”原则大大拓宽了新闻媒体的言论空间。在此后的诸多判例中，法院对“公众人物”的界定和适用范围经过了较为复杂的演变，也得到了相对确定的认识，对此国内外学者已做过相对充分的介绍和讨论，而对与之一起适用的“实际恶意”规则的探讨相对较少。本文以“马森诉《纽约客》杂志案”为例，围绕本案审理中的“实际恶意”规则运用进行分析，并对该规则在普通法上的实体内涵进行界定，分析该法则的客观证明方式，并解析该规则对诽谤诉讼中的程序法带来的改变。

After the judgment of the New York Times Co. v. Sullivan in 1964, American defamation law has changed from traditional nature of the common law to constitutionalization of the defamation law. The principle of “public figure” established in the case greatly broaden the space for speech. The definition and scope of the public figure by the court have undergone a complicated evolution, and they have also been relatively well recognized. In this regard, scholars from domestic and abroad have made a relatively sufficient introduction and discussion, but few of them discuss the application of “actual malice” rule. The paper takes Masson v. New Yorker Magazine, Inc. as an example to focus on the application of “actual malice” rule and its’ connotation in the common law, and analyze the objective proof of the rule and changes to the procedural law in libel action.