It is now commonplace for people to be charged with crimes where there are no victims. A car is speeding, maybe 10 miles over the posted speed limit, but maintains complete control of their vehicle. A cop pulls the car over and issues a ticket, which then results in either a payment from the 'offender' or that person showing up in court and wasting time and money. Who is harmed? Who is the victim? The only victim in this example is the police officer's pride (and of course the driver).
Let's say there is a person who likes to go home at night and smoke some marijuana, never leaving their home, where they live alone. Some police walk by on the sidewalk, and smell a funny odor coming from the house. Fearing destruction of evidence, they break down the door (without a warrant), and arrest the homeowner. Who is harmed? Who is the victim?
Hopefully you're with me so far. What about someone who is driving drunk? Let's say that a person enjoyed enough adult beverages to put themselves over the stated legal limit. While driving, they are obeying all traffic signals and give no indication of being incapable of driving. At a DUI Checkpoint, the police determine the driver is over the legal limit, though shows no signs of being drunk. The driver is arrested, the car is towed and the license is suspended. After a court hearing, classes are mandated. Who is harmed? Who is the victim?
But wait, you say, aren't these behaviors we want to discourage? No, I say. I have no problem with anyone's actions as long as they do not harm anybody else. If somebody wants to smoke crack and lose all their teeth and worse, go for it, have fun. If a young boy wants to go to school in a dress, go for it, have fun. None of these things bother me. What bothers me is our police force and court system taking it into their hands to punish people who might cause harm. You either cause harm or you don't, you can't be somewhere in the middle.
Ok, so if we get rid of all the preventative laws what happens to the person who drinks and drives and kills somebody? Instead of preventative laws, we need a tiered punishment for existings laws where harm is involved. If somebody drove drunk and killed someone, the punishment would be in a higher tier than somebody who wasn't drunk, just for an example. If you were speeding and hit another car, your punishment might be 10% more severe than someone driving the speed limit, and so on. The tiers could be linked to how many miles over the speed limit they were traveling or how many points over the "legal limit" they were.
Preventative laws only prevent one thing: freedom. They do little to deter those who would push the limits to the point of harming others. More severe penalties for those who lose control of themselves would be a great deterant, and even better, it would allow for the maximum freedom to be enjoyed by the population. As a society, we can't punish people for what they might do, even if what they are doing seems wrong to bystanders. As long as they are harming nobody but themselves, I say they should be free to pursue whatever happiness they desire.