A few observations:

• Literally 100% of people who ever lived have done multiple things which unfriendly legal system might treat as crimes, starting from simple ones like watching youtube videos uploaded without consent of their copyright owners, making mistakes on tax forms, reckless driving, defamation, hate speech, and going as far as the legal system wants to go.
• Vast majority of suspects in US do not get any trial whatsoever, they're forced to accept punishment or risk vastly higher punishment if they want to take their chance of trial.
• There are good reasons to believe few trials that happen are extremely far from any kind of fairness, and they're stacked to give persecution an advantage. Just compare massive funding of police and prosecutors with puny funding of defense attorneys.
• US has extraordinarily high number of prisoners per capita. Looking at crime rates alone, it does not have extraordinarily high levels of serious crime per capita. There's no way most people in prisons can be anything but innocent (or "guilty" of minor and irrelevant "crimes" pretty much everybody is "guilty" of and persecuted on legal system's whims).
• Unless you believe that young black men in US are the most criminal group in history of the world, most of them who are in prisons must be innocent by pure statistics.