There are other questions on Law.SE asking about specific hypotheticals related to the double jeopardy rule, but are there any concrete, actual recorded cases of anyone, in all of history, in any common law jurisdiction where:
How can you know for sure?
Let's say I'm charged with, and acquitted of, murder. Immediately after my acquittal, I confess to the crime describing how I did it and producing tangible and material evidence like the murder weapon, etc. So, did I commit murder? Well, we can't say. All we can say is that if I were tried again with all this new evidence, I'd probably be convicted but we can never know for sure because that trial isn't going to happen.
On the other side of the ledger, Michael Weir was the first person convicted after the UK changed its double jeopardy laws in 2005 allowing the Court of Appeal to grant a retrial if "new, compelling, reliable and substantial evidence" had emerged.
The Mel Ignatow case is probably among the most famous. There was also a case in Texas more recently, though double jeopardy was triggered by a conviction for a lesser included offense, rather than a conviction..
In 1941 a 14 year old boy in the USA was brutally tortured and murdered. He was acquitted by the probably biased jury. After their acquittal the group spoke openly about their deed in an interview, confident and without worry, knowing they would never get convicted, because of double jeopardy laws.
A man who raped and killed a 17 year old girl in Germany 30 years ago stood trial back then and was convicted to a lifetime prison sentence, but later in an appeal trial had to be acquitted as it was determined that the evidence was not beyond reasonable doubt.
Then 21 years later, or 9 years ago now, a DNA analysis of a sperm sample collected from the victim, which wouldn't have been possible back then, provided clear and convincing evidence for his guilt. But another prosecution was not allowed, because it would have been double jeopardy. The (still unconvicted) rapist and murderer Ismet H. still walks around scot-free.
A change in legislation seem to be finally underway after public petitions led by the victim's father, seeking to make repeated prosecution in the light of new evidence allowable in cases of grievous crimes like murder or genocide. But it is not finalized yet.
Short Answer Laws are codified in statutes, so don't worry about the label "common law jurisdiction." Nevertheless, we're not dealing with common law. Your answer is in the 5th Amendment.There's no "concrete case" (we call this caselaw) because the scenario you propose is not possible. Once a defendant is acquitted in state court, the state("prosecuting agency")cannot try him/her again,for the same charges, regardless of what evidence comes out after. The prosecuting agency is barred from appealing the verdict. With no right to appeal, cases like the one you're looking for don't exist.If there is evidence of a different crime, or separate criminal transaction,then the double jeopardy clause doesn't apply because they're not the same offense. Also, beyond a reasonable doubt is always the burden of proof in criminal trials. And the hypothetical facts in your question would require probable cause not clear and convincing.
Examples Everywhere If you look at it differently, then there are thousands of concrete cases; anyone who has ever been acquitted. There are caveats to double jeopardy, such as whether the federal government can also prosecute or whether the new evidence is related enough to the originally charged offense(s), to constitute the "same offense." But that's beyond the scope of your question.
Rationale For The Double Jeopardy: Double jeopardy means that no person can be tried twice for the same offense. It's an absolute right, and is incorporated to the states through the due process clause in the 14th Amendment. No state can change it. The purpose of the right is to create finality in criminal proceedings. Without it, the government would have unlimited chances to prosecute the accused.
Fact Pattern related to your question Suppose A gets into a fight with B on January 1, 2021. A is charged with assault and related charges. At this stage the double jeopardy clause is not applicable. It is triggered when a jury is sworn in or when the prosecutor begins it's case in chief for a bench trial (judge is fact finder not jury). A is acquitted on all charges. A few days after the acquittal a video comes out showing A hitting B with a gun during the fight. The gun has A's DNA and fingerprints all over it. Plus A confesses to the whole thing. What then? Nothing. It doesn't matter because A was acquitted. And yes, this scenario falls within the same offense because it arises out of the same criminal transaction. Whatever A was charged with is secondary to the criminal conduct A was arrested for. Thus, the prosecutor is barred entirely from trying A for any conduct on January 1, 2021, regarding the fight.
