Despite the importance of the speedy trial principle in criminal law procedure, few Supreme Court decisions have delineated its scope. In Barker v. Wingo, the Court established a balancing test that examines the interests and conduct of both prosecution and the defendant but refused to hold that the Constitution requires an individual to be tried within a specified period. However, the Court imposed a more stringent test for postindictment delay in United States v. Marion. The speedy trial right of one who violates a State or Federal statute attaches on the date of arrest or indictment. The Court has upheld that an individual can be prosecuted by both State and Federal governments for the same offense but has not considered if the speedy trial right of one accused of a Federal crime could ever be attached prior to the date of Federal arrest when a State arrest based on the same illegal activity has previously occurred with the acquiescence of the Federal Government. Resolution of this problem is currently within the discretion of the individual circuit courts. An examination of the Speedy Trial Act emphasizes that it applies to different processing stages and establishes different criteria for dismissals than the Court's decisions. Critical comments of jurists on the dual sovereignty theory which permits multiple prosecutions are discussed, followed by a review of differing approaches taken by circuit courts in multiple prosecution cases. One court held that the sixth amendment speedy trial right began once the Government accused the defendant, while others have liberally construed the commencement date of the speedy trial guarantee. The definition of 'basis of arrest' has continued to confuse the courts. An analysis of the United States v. Lai Ming Tanu in the Second Circuit illustrates judicial dissatisfaction with the current speedy trial aspects of the dual sovereignty theory. In view of the recognized harshness of multiple prosecutions, the Barker test requiring a finding of prejudice should be applicable to post-State arrest, pre-Federal indictment delays and permit the attachment of the speedy trial right before Federal indictment. The paper includes 94 footnotes.