In Waller v. Georgia, 1983, the U.S. Supreme Court ruled that a defendant's Sixth Amendment right to a public trial extends to pretrial suppression hearings. The case involved two defendants who were charged with various drug offenses in Georgia and requested their Fourth Amendment rights be reviewed during a pretrial hearing regarding the admissibility of certain evidence obtained through wiretaps. However, this hearing was closed to the public due to concerns about revealing confidential information related to informants and ongoing investigations. The defendants appealed on grounds that closing the courtroom violated their constitutional right for an open trial as guaranteed by the Sixth Amendment. The Supreme Court agreed with them in a unanimous decision stating that before excluding members of the public from any stage of criminal proceedings - including pre-trial motions - courts must consider whether alternatives would protect interests at stake without infringing upon open trials; if closure is necessary it should be no broader than required; and findings supporting closure must be made on record.

In the dissenting opinion for Waller v. Georgia, Justice Powell argued that the majority's decision to require open preliminary hearings was not supported by constitutional text or precedent. He contended that the Sixth Amendment right to a public trial did not extend to pretrial proceedings such as suppression hearings because they are fundamentally different from trials in their purpose and effect on defendants' rights. Additionally, he pointed out that historically, these types of proceedings have been closed without controversy or challenge under the Constitution. Furthermore, he expressed concern about potential negative effects of this ruling on privacy interests and fair trial rights due to increased publicity during early stages of criminal cases which could influence jury pools and witnesses. Overall, while acknowledging transparency is important in judicial process generally speaking; Justice Powell believed it should be balanced with other considerations like protecting defendant’s right against prejudicial publicity.