Also known as: ne bis idem · non bis in idem · double jeopardy
Written by attorneys · grounded in primary & secondary sources — see below
A principle of law that bars successive prosecutions or punishments for the same offense after jeopardy has attached in a court of competent jurisdiction. The bar prevents the government from retrying a defendant for conduct already adjudicated on the merits or for lesser included offenses arising from the same facts.
After a jury convicted Nyah Ndlovu of felony assault arising from a single altercation, the state filed a new information charging her with misdemeanor battery based on identical facts. The trial court dismissed the misdemeanor charge because the prior conviction for the greater offense already resolved the same conduct.
Natalie Norris was acquitted in federal court on drug-trafficking charges. State prosecutors then filed identical charges in state court based on the same transactions. The state court dismissed the indictment because the federal acquittal triggered the double-jeopardy protection incorporated against the states.
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Nathaniel Newman faced trial on robbery charges. After the jury was sworn, the judge declared a mistrial over defense objection because a key witness failed to appear. When the state sought to retry him, the court granted dismissal because jeopardy had attached and no manifest necessity justified a second proceeding.
Nikhil Narayan was convicted of conspiracy to distribute narcotics. Prosecutors later charged him with the underlying distribution offense based on the same transactions. The court dismissed the new charge because the prior conspiracy conviction already encompassed the same conduct under the applicable double-jeopardy analysis.
Nigel Nelson was acquitted of murder in state court. The state appealed and obtained reversal on a legal error. On remand the trial court refused to permit retrial because the original acquittal had terminated jeopardy and the Double Jeopardy Clause barred further prosecution.
Naveen Nanda was acquitted in federal court of firearm possession by a felon. State prosecutors then filed an identical charge under state law. The state court denied dismissal because the federal and state governments are separate sovereigns and each may prosecute the same conduct without violating the principle.
No. A proceeding before a tribunal without authority over the offense does not count as a former prosecution that triggers the bar. The earlier judgment is treated as a nullity for double-jeopardy purposes.
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Jeopardy attaches when the jury is empaneled and sworn. Once attachment occurs, a subsequent prosecution for the same offense is barred unless the first proceeding ended in a manner that permits retrial, such as a reversal for trial error.
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Yes. After a defendant has been prosecuted for a greater offense, the principle prohibits a later prosecution for a lesser included offense based on identical facts.
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Yes. The Double Jeopardy Clause does not bar successive prosecutions by different sovereigns, such as the federal government and a state, even when the charges rest on identical facts.
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No. When the defendant elects to sever charges that could have been tried together, the first trial does not bar subsequent trials on the remaining charges under the principle.
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…of acquittal could be overturned and a defendant retried would run afoul of the Sixth Amendment jury-trial guarantee and the Double Jeopardy Clause of the Fifth Amendment. In the federal system it also would be unconstitutional to prohibit a President from deciding, as an act of executive clemency, to reprieve one sentenced to…