It doesn't, and this LEO apologist narrative around here is what keeps things like this in place. This belief that such actions are the result of the victim's stupidity, and not the legal practices and judicial system that enable and ultimately legalize what amounts to theft is the source of the problem.
I feel bad for the elderly man, he came from a period where inherit Trust in law enforcement was basically the norm, perhaps ignorant and naive, but it can't help but underscore the times we live in.
For those who have never had anything taken away from them from Police its hard to explain the vulnerability and exposed sense of betrayal it leaves you with, especially when you're proven innocent. It makes you take so many precautions before leaving your home, not against the most cunning and slick of thieves, but those legally sanctioned to do so.
Also, I think the police in the USA right now are FAR more professional than they were when this guy was born. They literally didn’t use fingerprints or most kinds of forensic evidence. It was largely about picking up the person that most tweaked your spidey-sense and trying to work backwards from there. Today we have FAR more traceability of chain of evidence and documentation of actions by individual officers than ever before. I’m not apologizing for officers or bad policy, I just want to give credit where I think not enough is given.
It might still be a bad idea. I don't know what has changed since, but this source (0) says fingerprinting hasn't been subjected to scientific review.
[0] : https://www.sciencedaily.com/releases/2017/10/171005111100.h...
The reason much of it works at all is because it gets applied primarily where there is a lot of other extremely traditional evidence (witnesses, motive, etc.).
Overconfidence in science-theater investigations have been resulting in more calls for dragnet operations, which would have extremely bad results.
It's not right, it's not ok, but tragically it continues to be legal.