I know a lot of people have theories about Jack the Ripper, even people who weren’t ever considered by 19th century police. There’s no way that case can get marked as solved though.
I’m curious though if there are any less profile older cases that using modern day methods and with enough remaining evidence, we can mark as “solved” even though it remained unsolved back in the day, and obviously the perpetrator is centuries dead?
I don’t think it will ever be solved but it’s theoretically possible though. Say if someone stumbled upon an old diary of the Ripper for instance. It’s a long shot but there may be a way.
My wife and I watch a lot of crime shows, 30-40 year old cases is not that uncommon with the advent of DNA.
Yeah, every few years someone “solves” the Jack the Ripper case, and it’s always a different person (at about the same frequency, someone usually “finds” Emilia Earhart, and similarly, she’s always in a different place).
The murder of Maria Ridulph is often cited as the oldest cold case that has been solved (1957 to 2012), but a review of the evidence showed that Jack McCullough (the supposed murderer) could not have been present for the crime, and in 2016 McCullough was declared innocent. This murder still shows up on a lot of web sites as the oldest cold case solved, even though that has been shown to be incorrect.
The murder of Wendy Jo Halison could be a contender. She was murdered in 1968 and the killer was identified in 2016. Edwin Dean Richardson was already dead by the time he was identified as the murderer. Richardson had been convicted of killing two women and was suspected of killing more.
Related cold thread.
Not really a “case” per se, but would the Shroud of Turin count ?
Do you mean the identity of the forger? Yes, it’s been demonstrated to be a forgery, but AFAIK who did it is unknown. I wouldn’t count that as “case solved.”
OK, not that I’m objecting to people talking about what they want to talk about, but I really wasn’t interested in 20th century cases.
I was hoping that some 15th century Venetian noble had been murdered and his skeleton combined with just enough information about peoples actions in the written accounts indicated the killer in a way that contemporary investigators would never have managed.
I was going to mention Otzi the Iceman, but while we have discovered that he was killed by an arrow, we don’t know who shot it. Still, a case doesn’t get much colder (heh) than that one.
I think as you go back farther in time, when there was nothing like modern police forces or investigation techniques, there will be definitional arguments about what a “case” is. If an archaeologist discovers an ancient grave with evidence that shows how the person was killed, even who killed him, is that solving a “case”?
I meant demonstrating it was a forgery when it had been considerer authentic for centuries (although, amusingly, not when it was actually produced)
There’s much older evidence of murder, such asthis one from 33,000 years ago, but of course we don’t know the identity of either the victim or his killer, other than that he was left-handed.
Actually, it was denounced as a forgery when it was first securely recorded.
The oldest case I’m aware of where there has actuallly been a conviction is the 1966 murder of Yolande Waddington in Berkshire, UK. The killer was convicted in 2012 due to DNA evidence. He had actually been serving a life sentence since 1967 for two other murders, a gap of 46 years.
Does it have to be a murder? The affair between Thomas Jefferson and Sally Hemmings was widely suspected at the time, but it was only in the late 20th century that it was confirmed by DNA evidence. And before anyone says it wasn’t a crime, Virginia probably had a law against adultery at the time.
Well, then we know who it wasn’t - but tell me this - did the victim have 6 fingers on his right hand? If so, maybe the murderer was just taking his time with him.
Does Richard III count? Discovered his body 527 years later. We knew he was killed in battle but not all the circumstances - contemporary accounts suggested death by halberd, they also found multiple other injuries on the skeleton. We still don’t know who did it - Rhys ap Thomas is credited in some sources. But it probably doesn’t matter.
Nope, any case is fine. Good example.
Easter is cancelled - they found the body! 
For a long-unsolved mystery, I’ll point to the discovery that the supervolcano eruption of Thera aka Santorini a few millennia ago explains the submergence of Atlantis (Minoan empire collapse) and the parting of the Reed Sea where “Pharaoh’s army got drownded.” Or if creation is a “cold case,” the Big Bang theory solves it.
I’m not sure adultery would be the applicable offense. As Uncle Cecil noted when he weighed in, Jefferson’s wife Martha died before the affair apparently began.
Cain, in the wheat field, with an Acheulean handaxe. 
Years ago they found the bodies of the two princes killed by Richard under the stairway in the Tower.