system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: solving old cases like Jack the Ripper

I remember how i would hear, from time to time, that some new information about, lets say Jack the Ripper, appeared and the case about him changed on some way. Same thing on John Wilkes Booth, Napoleon and other people from way more than 100 years ago. How can something from so much time in the past still change? Wich kind of evidence is this and how people get it? Investigations are still happening? Can we trust the new information?
gpt
To put it simply, we have better tools to analyze the historical records now and communicate things that seem strange in them. Or records previously undiscovered turn up. Or new general knowledge happens that explains anomalies that people at the time couldn't (like scientific advances). Also, in the case of criminals specifically, the subject being analyzed is no longer able to fight back and destroy evidence.