## Facts

- Raymond Downum was federally indicted with three others on eight counts involving theft from the mail and forging and uttering stolen checks.
- The codefendants pleaded guilty; Downum proceeded to trial alone.
- At the first trial setting, both sides announced ready, a jury was selected and sworn, and the jurors were told to return later that day.
- When the jury reconvened, the prosecutor sought discharge of the jury because a key witness for certain counts (the checks’ payee) was not present.
- Downum objected, moved to dismiss the affected counts for lack of prosecution, and asked to proceed on the remaining counts.
- The district court denied the request and discharged the sworn jury over Downum’s objection.
- Two days later, a second jury was impaneled; Downum pleaded former jeopardy, the plea was overruled, and he was convicted.
- The court of appeals affirmed; the Supreme Court granted review and reversed.

## Issues

1. Whether the Double Jeopardy Clause bars reprosecution when the first jury was sworn and then discharged over the defendant’s objection due to the prosecution’s missing witness.
2. Whether the absence of a prosecution witness, known to be missing when the government proceeded to swear the jury, constitutes “manifest necessity” permitting a mistrial and retrial.

## Decision

- The Supreme Court reversed.
- Jeopardy had attached when the first jury was selected and sworn.
- Discharging the jury due to the prosecution’s absent witness, under these circumstances, was not justified by manifest necessity.
- Downum’s plea of former jeopardy should have been sustained, and the second trial was barred.

## Legal Principles

- Jeopardy attaches in a jury trial when the jury is empaneled and sworn.
- A mistrial declared over the defendant’s objection permits retrial only when there is “manifest necessity” for ending the first trial without a verdict.
- The prosecution’s failure to secure a key witness—when it nonetheless proceeds to have the jury sworn—does not amount to manifest necessity and cannot justify retrial.
- The Double Jeopardy Clause prevents the government from aborting a trial after jeopardy attaches to cure deficiencies in trial readiness and then retrying the defendant.

## Conclusion

Because the government proceeded to swear a jury while lacking a key witness and then sought a mistrial when that witness did not appear, the mistrial lacked manifest necessity; the Double Jeopardy Clause therefore barred Downum’s retrial and required reversal of his conviction.


Downum v. United States, 372 U.S. 734 (1963)