What are the factors used to determine whether a defendant has been deprived of his right to a speedy trial?

The court in Barker v. Wingo identified four factors which should be considered in assessing whether a defendant has been deprived of his right to a speedy trial, and they are as follows: length of the delay, the reasons for the delay, the defendant’s assertion of his right to a speedy trial, and finally, prejudice to the defendant. In considering the manner in which these factors should be considered Powell, J., said at p. 530 (407 US 514) and p. 117 (33 L Ed 2d 101): The length of delay is to some extent a triggering mechanism. Until there is some delay which is presumptively prejudicial, there is no necessity for inquiry into the other factors that go into the balance. Nevertheless, because of the imprecision of the right to speedy trial, the length of delay that will provoke such an inquiry is necessarily dependent upon the peculiar circumstances of the case. To take but one example, the delay that can be tolerated for an ordinary street crime is considerably less than for a serious, complex conspiracy charge. Closely related to length of delay is the reason the government assigns to justify the delay. Here, too, different weights should be assigned to different reasons. A deliberate attempt to delay the trial in order to hamper the defense should he weighed heavily against the government. A more neutral reason such as negligence or overcrowded courts should be weighed less heavily but nevertheless should be considered since the ultimate responsibility for such circumstances must rest with the government rather than with the defendant. Finally, a valid reason, such as a missing witness, should serve to justify appropriate delay. We have already discussed the third factor, the defendant’s responsibility to assert his right. Whether and how a defendant asserts his right is closely related to the factors we have mentioned. . . The defendant’s assertion of his speedy trial right, then, is entitled to strong evidentiary weight in determining whether the defendant is being deprived of the right. We emphasize that failure to assert the right will make it difficult for a defendant to prove that he was denied a speedy trial. A fourth factor is prejudice to the defendant. Prejudice, of course, should be assessed in the light of the interests of defendants which the speedy trial right was designed to protect. This court has identified three such interests: (i) to prevent oppressive pretrial incarceration; (ii) to minimize anxiety and concern of the accused; and (iii) to limit the possibility that the defense will be impaired. Of these, the most serious is the last, because the inability of a defendant adequately to prepare his case skews the fairness of the entire system. If witnesses die or disappear during a delay, the prejudice is obvious. There is also prejudice if defense witnesses are unable to recall accurately events of the distant past. Loss of memory, however, is not always reflected in the record because what has been forgotten can rarely be shown.