Great example of Capone being a known criminal but there being little evidence against him. It’s similar to anyone in the mob. That’s why RICO was established as a crime, and why there was talk about it being applied to Trump aids so they would testify.
It's interesting that courts, trials, and the entire legal process can change depending on the expense of the lawyers involved. Most accused suspects probably can't afford an attorney, so they end up with a public defender. Someone in that position might get easily railroaded by the justice system.
But someone who can afford a big time, expensive lawyer who has a big staff, who will work diligently and find every possible loophole - and who knows how to game the system well - then the advantage shifts to the defense. The OJ case is a perfect example.