In the United States v. MacDonald case of 1977, the U.S Supreme Court ruled that a military officer could not use his right to a speedy trial as grounds for dismissal of charges against him. The defendant, Jeffrey R. MacDonald, was an Army doctor accused of murdering his wife and children in 1970 but wasn't formally indicted until 1975 due to ongoing investigations by both military and civilian authorities. He argued that this delay violated his Sixth Amendment rights to a speedy trial. However, the court disagreed stating that these rights were not applicable because he had been discharged from the army before being charged with any crime; thus making him technically a civilian at time of indictment and subjecting him to different legal standards than those applied while he was still serving in the military.

In the dissenting opinion for United States v. MacDonald, Justice Brennan disagreed with the majority's interpretation of the Speedy Trial Clause of the Sixth Amendment. He argued that it should apply from the time a person becomes an "accused," which in this case was when formal charges were first brought against him by military authorities, not when he was indicted by a federal grand jury years later. Brennan believed that MacDonald had been denied his right to a speedy trial due to significant delays between his initial accusation and eventual indictment and trial. The justice also criticized how these delays could potentially harm defendants' abilities to defend themselves effectively as evidence may become lost or degraded over time, memories may fade, and witnesses might disappear or die. Furthermore, Brennan expressed concern about potential abuses of power where prosecutors could manipulate proceedings through strategic timing of indictments.