Is there any way to undo a “not guilty” verdict by a jury in a criminal trial?

No. As you said, “same act”. The jury had the option of finding him guilty on a lesser charge like manslaughter; they didn’t, they said Not Guilty. So any criminal charges for that act by that authority are concluded.

As mentioned, they could later be charged by a different authority, like Federal charges for that same act. But different charges, like killing a Federal agent, violating the civil rights of a citizen, etc.

They could also be sued in Civil Court for damages caused by that same act. But that’s a private lawsuit by a wronged party, not a criminal prosecution. And generally, having been already found not guilty in a criminal case can be used by the defense in the civil lawsuit, and is a pretty strong defense. But not always enough, for example, in the OJ civil case.

I recall a case where that exact thing happened, a defendant was found not guilty, then proceeded to taunt the DA with the fact that he did do it and was subsequently retried and found guilty. Apologies for not being able to find it now. Would that fall under the heading of “new evidence”?

Darn you, Siam Sam, I came to cite the same case.

AIUI, the second time it was murder with special circumstances, and eligible for the death penalty. Double Jeopardy didn’t apply because it was a more serious crime than the original trial.

What’s the opposite of “lesser included offenses?”

Here in the U.K., someone found Not Guilty can be retried if compelling new evidence arises.

See http://www.cps.gov.uk/legal/p_to_r/retrials/ - Re-trial under Part 10 Criminal Justice Act. Note also the issue of a tainted acquittal. I’m sure Ak84 can give us chapter and verse.

Following the U.K. political precedent, same in Vic.Aus (and some other states).

When a crime is “held back,” it’s usually strategic and legal, and there’s something about it that distinguishes it from other acts committed in the same larger incidence.

For example, a woman named Darlene Routier was accused of killing two of her sons. Because of their ages, the murder of one of the sons, who was younger than 7, carried a death penalty, without any other “aggravators” (like rape or torture), because killing a child under 7 alone is an aggravating circumstance. He other son was about 18 months older, and too old for the death penalty to be automatically applied.

So initially, she was tried only for the son who was under 7. The plan was that if that trial was lost, or ended with anything less than life without parole, then she would be tried for the murder of the other child.

Last time I checked, she was on death row, but still going through appeals. She still hasn’t been tried for the murder of her other son, and won’t be, if her execution is carried out, or if the appeal commutes her sentence to life without parole. If she gets life with parole, she may be tried for the other murder, and the prosecutor will ask for life without parole. Even if she gets a second sentence of life with parole, if she is serving two of them, the chance that she ever actually gets paroled is highly unlikely, especially as she can be made to serve the sentences consecutively, not concurrently, which means that if she were paroled on one sentence, she’d just begin the other one. She’d have to win parole twice, after serving whatever it took to be allowed to apply for parole (15, or 25, or 40 years, or whatever), TWICE.

But the murders of her sons, while one incident, were two acts. So this is legal. If she’d won at trial when tried for the first murder, it wouldn’t have been double jeopardy to try her for the second murder. It WOULD have been double jeopardy to try her for manslaughter under a different theory of the crime if she’d been acquitted of first degree murder the first time.

When you’re testifying in court after having sworn an oath to tell the truth, the whole truth, and nothing but the truth, you do not have the right to lie your ass off. See perjury, for which the penalties can be severe.

I think you folks are thinking of Paul Warner Powell. He was tried and acquitted for raping one sister and murdering another. Since these were legally considered two separate offenses, the murder charge didn’t carry the risk of a death penalty. Powell then wrote a taunting letter to the prosecutors, in which he confessed to the crimes, and admitted to attempting to rape both sisters. In doing so, he basically confessed to felony murder (murder committed in the course of the rape of the second sister). He was re-tried on that charge, and eventually executed.

An example: Mel Ignatow, who was acquitted of murder but then tried and convicted for perjury after photographic evidence of the crime was discovered.

Oddly enough, this was the case that I was thinking of when I made my original post.

So if a defendant chooses to testify, he will be obliged to do so under oath?

IANAL, but I don’t believe anyone is allowed to testify in a criminal case without swearing an oath first.

That was in Britain, not the US. I seem to recall a couple of such cases (all in the UK), which are what led British lawmakers to change the law to allow for retrials if an acquitted person subsequently confesses.

In the US, such a thing is pretty much unheard of. The OJ Simpson book being about the only such incident that anybody can recall. And even then, the book is ostensably speculation on OJ’s part on how he would have done it, and not a confession. Not that this gimmick fooled anybody.

Well, yes. So is everyone else.

Technically, all witnesses have the option of swearing an oath or an affirmation (which is the same thing minus the god part.)

I think that Donnerwetter is posting from Germany. The civil law system takes a different approach to oaths than the common law system. My recollection is that an accused is not required to testify under oath in the civil system, in part because the principle against self-incrimination is more nuanced. In the common law system, it’s more black and white: the accused has the absolute right not to testify, but if he does, is required to do so under oath, just like any other witness.

Yes, that is correct. I was about to point out this major difference. In Germany (and AFAIK for instance in Austria), the defendant is allowed to lie with impunity when he takes the stand (with very few exceptions, for instance he cannot falsely accuse a third party of having committed a crime).

And I might add that I really was under the (wrong) impression that the right of the accused to lie on the stand is universal. I learned today that this is not the case. Ignorance fought. :slight_smile:

What they taught us in social studies class was that the option to “affirm” something was created because certain religious sects believed that you should only swear an oath to God, and shouldn’t swear an oath over any secular matter. To get around the issue, such people could choose to “affirm” the oath instead.

Has this ever happened, in a case that didn’t involve perjury or admittance of a further crime that could be followed up on?

As long as the defendant didn’t take the stand (or give a deposition), he can’t perjure himself.

That’s essentially true. Affirmations were originally adopted in English law to appease the Quakers. They were enough a part of the common law by the founding of the United States to make it into the Constitution. For example, Article II allows the POTUS to take an affirmation of office rather than an oath of office.