suspect has invoked those rights. Furthermore, a voluntary reply, even after lengthy silence, can be construed as implying a waiver. The new rule will defer to police in cases where the suspect fails to assert the right to remain silent. This standard was extended in Salinas v. Texas in 2013 to cases where individuals not in custody who volunteer to answer officers' questions and who are not told their Miranda rights. The Court stated that there was no "ritualistic formula" necessary to assert this right, but that a person could not do so "by simply standing mute". Production of documents Under the Act of Production Doctrine, the act of an individual in producing documents or materials (e.g., in response to a subpoena) may have a "testimonial aspect" for purposes of the individual's right to assert the Fifth Amendment right against self-incrimination to the extent that the individual's act of production provides information not already in the hands of law enforcement personnel about the (1) existence; (2) custody; or (3) authenticity, of the documents or materials produced. See United States v. Hubbell. In Boyd v. United States, the U.S. Supreme Court stated that "It is equivalent to a compulsory production of papers to make the nonproduction of them a confession of the allegations which it is pretended they will prove". By corporations Corporations may also be compelled to maintain and turn over records; the Supreme Court has held that the Fifth Amendment protections against self-incrimination extend only to "natural persons". The Court has also held that a corporation's custodian of records can be forced to produce corporate documents even if the act of production would incriminate him personally. The only limitation on this rule is that the jury cannot be told that the custodian personally produced those documents in any subsequent prosecution of him, but the jury is still allowed to draw adverse inferences from the content of the documents combined with the position of the custodian in the corporation. Refusal to testify in a criminal case In Griffin v. California (1965), the Supreme Court ruled that a prosecutor may not ask the jury to draw an inference of guilt from a defendant's refusal to testify in his own defense. The Court overturned as unconstitutional under the federal constitution a provision of the California state constitution that explicitly granted such power to prosecutors. Refusal to testify in a civil case While