According to https://ucr.fbi.gov, in 2015, there were "… an estimated 10,797,088 arrests." Further, "the highest number of arrests were for drug abuse violations (estimated at 1,488,707 arrests)," as well as "… driving under the influence (estimated at 1,089,171." Taking a closer look, at the drug-abuse violations, the majority of those arrests were for possession, that is actually having the illicit drug in one's home, car, or in hand, of which the drug most often arrested for possession, was marijuana, a drug that has been legalized in several States, decriminalized in several other States, or allowed to be utilized in several States if medically prescribed, yet, this is the drug that most often necessitates an arrest for possession, for the very simple fact, that the sheer amount of people that utilize or possess marijuana is a very large number to begin with. Additionally, so-called "driving under the influence" is one of the most pernicious laws ever foisted upon the public, for if any adult of legal age has a Blood Alcohol Concentration (BAC) of .08 percent or more they are considered to be "per se intoxicated", and incredibly some of those that have a BAC of under .08 percent can still be arrested for a DUI, if the officer perceives that they have been driving as if impaired, or their speech appears to be slurred. The reason the current DUI law is so pernicious, is that previously when BAC limits were first imposed to determine impairment, that limit was set at .15 percent, which argues the question, were the medical doctors and authorities, so stupid and ignorant in the 1980s that they clearly didn't know the difference between intoxication and non-intoxication or was the law inexorably changed in order to ensnare more people. Further to the point, automated cars are now allowed on the roads, so that being so, would a given intoxication level in a fully automated car even be relevant; in addition, there are cars manufactured today that have automated or semi-automated features such as "lane assist", "steering assist", "automatic forward-collision braking", and so on and so forth, which definitely are a real assistance to drivers of those cars, and should be relevant to any discussion of how impaired a driver with such features in use, actually was, especially if this is a considered to be a public safety issue.
In addition, there are all sorts of laws that people are arrested for of dubious value, which are better classified as victimless crimes, since there is no victim, only possibly a moral issue in regards to illicit drug usage, gambling, or prostitution; then there are nuisance crimes, which are things such as public intoxication, disorderly conduct, curfew, or loitering, which are arbitrary and often unfairly applied. There are, in short, an unseemly amount of arrests made each and every day for crimes in which there are either no victim, or a specific desire by the state policing authority to interfere with the life style choices that a particular person has made, as if it is the state that should have final say as to what is permitted or not permitted, recognizing that the state's power is so pervasive that they can effectively rule by fiat, empowered by laws that criminalize everything.
The way that the criminal justice system is constructed in America, today, is that it is an embedded institution that needs arrests and therefore criminals which makes it a thriving business, considered to be a real "growth industry". In point of fact, a significant portion of arrests being made today, could be far better resolved with far less trouble and far less expense, if the criminal violation, was amended to be something equivalent to receiving a traffic ticket, which while this would still be an inconvenience to the public, it would be a significant and meaningful step in the right direction of less arresting and thereby less incarceration. In a country that professes that it is "free", the reality of the situation for the average man in the street is that it most definitely is not "free", and it is not fair; it is instead highly intrusive, intolerable, unacceptable, and cruel.