# Can an acquitted defendant be charged with perjury later? **URL:** \ **Category:** Factual Questions\ **Created:** [November 12, 2004, 7:59pm UTC](https://boards.straightdope.com/t/can-an-acquitted-defendant-be-charged-with-perjury-later/274439 "2004-11-12T19:59:47Z")\ **Posts on this page:** 10\ **Page:** 1
**Author:** ![Hadrian0117](https://avatars.discourse-cdn.com/v4/letter/h/3d9bf3/32.png) [@Hadrian0117](https://boards.straightdope.com/u/Hadrian0117)\ **Post date:** [November 12, 2004, 7:59pm UTC](https://boards.straightdope.com/t/can-an-acquitted-defendant-be-charged-with-perjury-later/274439/1 "2004-11-12T19:59:47Z")
If a defendant testifies at his own trial and is found not guilty can the DA later prosecute him for perjury? Or would double jeopordy apply? Wouldn’t the DA have to prove he commited the crime the was originally charged with after he was found not gulity of it? ---
**Author:** ![OldGuy](https://avatars.discourse-cdn.com/v4/letter/o/3bc359/32.png) [@OldGuy](https://boards.straightdope.com/u/OldGuy)\ **Post date:** [November 12, 2004, 8:46pm UTC](https://boards.straightdope.com/t/can-an-acquitted-defendant-be-charged-with-perjury-later/274439/2 "2004-11-12T20:46:36Z")
> [@Hadrian0117](#): > > If a defendant testifies at his own trial and is found not guilty can the DA later prosecute him for perjury? Or would double jeopordy apply? Wouldn’t the DA have to prove he commited the crime the was originally charged with after he was found not gulity of it? IANAL but i’d think you could convict him with perjury for lying abut some things incidental to the crime. For example, if he lied about an alibi and you later could prove he’d lied, I’d think you could charge and convict him on that. You could not convict him of perjury for saying he didn’t commit the crime. By the previous finding of a court he did not in fact do so. If you even tried to present evidence he’d committed the crime, it would properly be objected to as an already established matter and not subject to retrial. For more information you want to look up the legal terms res judicata (Latin for “the thing has been decided”) more commonly called “claim preclusion” in English and collateral estoppel more commonly called “issue preclusion” in English. ---
**Author:** ![Xema](https://avatars.discourse-cdn.com/v4/letter/x/9de053/32.png) [@Xema](https://boards.straightdope.com/u/Xema)\ **Post date:** [November 12, 2004, 9:50pm UTC](https://boards.straightdope.com/t/can-an-acquitted-defendant-be-charged-with-perjury-later/274439/3 "2004-11-12T21:50:09Z")
> [@OldGuy](#): > > You could not convict him of perjury for saying he didn’t commit the crime. By the previous finding of a court he did not in fact do so. But that court found him “not guilty” which is not the same thing as saying he didn’t do it. It could well be the case that the jury believed he _did_ do it, but also that the prosecution failed to prove this beyond reasonable doubt. So, since IANAL, I ask: is it true that a “not guilty” verdict can be used as subsequent legal evidence of innocence? Would not this have been an excellent line of defense in the OJ civil trial? ---
**Author:** ![Hadrian0117](https://avatars.discourse-cdn.com/v4/letter/h/3d9bf3/32.png) [@Hadrian0117](https://boards.straightdope.com/u/Hadrian0117)\ **Post date:** [November 12, 2004, 10:07pm UTC](https://boards.straightdope.com/t/can-an-acquitted-defendant-be-charged-with-perjury-later/274439/4 "2004-11-12T22:07:28Z")
> [@Xema](#): > > But that court found him “not guilty” which is not the same thing as saying he didn’t do it. It could well be the case that the jury believed he _did_ do it, but also that the prosecution failed to prove this beyond reasonable doubt. > > So, since IANAL, I ask: is it true that a “not guilty” verdict can be used as subsequent legal evidence of innocence? Would not this have been an excellent line of defense in the OJ civil trial? A “not guilty” verdict isn’t legal evidence that one is innocent; it just means the jury wasn’t conviced of the defendants guilt _beyond a reasonalbe doubt_, one can still be found at fault in civil court since the standard there is _preponderance of evidence_. ---
**Author:** ![barbitu8](https://avatars.discourse-cdn.com/v4/letter/b/839c29/32.png) [@barbitu8](https://boards.straightdope.com/u/barbitu8)\ **Post date:** [November 12, 2004, 10:49pm UTC](https://boards.straightdope.com/t/can-an-acquitted-defendant-be-charged-with-perjury-later/274439/5 "2004-11-12T22:49:30Z")
> [@OldGuy](#): > > For more information you want to look up the legal terms res judicata (Latin for “the thing has been decided”) more commonly called “claim preclusion” in English and collateral estoppel more commonly called “issue preclusion” in English. _Res judicata_ and _collateral estoppel_ are terms applicable only to civil law, not criminal law. For _res judicata_, to apply, there must be identity in thing sued for as well as identity of cause of action, of persons and parties in action, and of quality in persons for or against whom claim is made. _Collateral estoppel_ provides for conclusiveness of judgment in prior action where subsequent action is upon a different cause of action but between the same parties and the same facts. (The issue is different.) _Double jeopardy_ refers not to the same offense but to the same crime, transaction or omission. SCOTUS has decided that it also must be in the same juridiction. That is, one tried under state law can be tried again under a federal law, even though it involves the same facts, transaction, etc, since it does not refer to the same offense or crime. That is the situation in the OP. Criminal libel is a different crime than whatever the defendant was initially acquitted of. ---
**Author:** ![Mr.Slant](https://avatars.discourse-cdn.com/v4/letter/m/c57346/32.png) [@Mr.Slant](https://boards.straightdope.com/u/Mr.Slant)\ **Post date:** [November 12, 2004, 11:00pm UTC](https://boards.straightdope.com/t/can-an-acquitted-defendant-be-charged-with-perjury-later/274439/6 "2004-11-12T23:00:42Z")
How about a prosecution witness, or complainant? Can false statements or charges by the other side made to the police, DA, etc be perjury, or would those just be libel? ---
**Author:** ![pravnik](https://avatars.discourse-cdn.com/v4/letter/p/8edcca/32.png) [@pravnik](https://boards.straightdope.com/u/pravnik)\ **Post date:** [November 12, 2004, 11:19pm UTC](https://boards.straightdope.com/t/can-an-acquitted-defendant-be-charged-with-perjury-later/274439/7 "2004-11-12T23:19:49Z")
> [@Jonathan Woodall](#): > > How about a prosecution witness, or complainant? > Can false statements or charges by the other side made to the police, DA, etc be perjury, or would those just be libel? Perjury is when you’re lying under oath. Lying to investigators falls under various obstruction of justice charges. ---
**Author:** ![DrDeth](https://avatars.discourse-cdn.com/v4/letter/d/b487fb/32.png) [@DrDeth](https://boards.straightdope.com/u/DrDeth)\ **Post date:** [November 13, 2004, 12:18am UTC](https://boards.straightdope.com/t/can-an-acquitted-defendant-be-charged-with-perjury-later/274439/8 "2004-11-13T00:18:35Z")
AFAIK, and IANAL- the DA can’t even charge them for perjury if they got on the stand and said “I am innocent, I didn’t do it” and they _were_ convicted. I think there is an exception for the defendant saying simply “I am not guilty” more or less. ---
**Author:** ![Peter\_Morris](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/peter_morris/32/359_2.png) [@Peter\_Morris](https://boards.straightdope.com/u/Peter_Morris)\ **Post date:** [November 13, 2004, 1:11am UTC](https://boards.straightdope.com/t/can-an-acquitted-defendant-be-charged-with-perjury-later/274439/9 "2004-11-13T01:11:44Z")
When the defendant pleads “guilty” or “not guilty” he isn’t under oath. Pleading “not guilty” when you are really guilty isn’t lying under oath, and therefore not perjury. ---
**Author:** ![DrDeth](https://avatars.discourse-cdn.com/v4/letter/d/b487fb/32.png) [@DrDeth](https://boards.straightdope.com/u/DrDeth)\ **Post date:** [November 13, 2004, 1:32am UTC](https://boards.straightdope.com/t/can-an-acquitted-defendant-be-charged-with-perjury-later/274439/10 "2004-11-13T01:32:14Z")
Like I said " if they got on the stand and said “I am innocent, I didn’t do it”.