I wonder how many millionaires there are who have done a white collar crime once, got their money, cleaned it using some business and now living off it never to do it again. Take that secret to the grave.
Not just white collar, but many people go missing never to be found. So I assume there are likely competent murders who understand enough of biology and chemistry to not leave a forensic trail and not attract too much attention.
This has some interesting bounds on it. Smart criminals are harder to catch, but the thing about crime is that it rarely actually pays to commit crimes. Most organized crime works by scamming other people into committing the high-risk crimes for you. So at some point the smart criminals realize they're the mark and either become informants or move on to legitimate business.
But just as petty crime has its bounds, so does legitimate business. This is why you have big tech companies that built their empires on lies and fraud. The justice system isn't optimized to catch this kind of crime, so it takes longer to get punished, and meanwhile every one of your competitors either learns to commit the same crimes or goes bankrupt. Furthermore the kinds of crimes you can commit once you've built a legitimate business are a lot more subtle and more lucrative.
So you have a society with an honest core of people doing the actual productive work, while being scammed by incredibly corrupt CEOs, who themselves distract the honest core with fears of petty criminals so that the justice system continues to expend its budget on cheap wins against the common crook.
In America, across the board, you could be as much as 50% capable of getting away with any murder you commit, of course, assuming that you don't directly implicate yourself somehow.
While the rate at which murders are solved or "cleared" has been declining for decades, it has now dropped to slightly below 50% in 2020 - a new historic low. And several big cities, including Chicago, have seen the number of murder cases resulting in at least one arrest dip into the low to mid-30% range.
