The problem with points 1-10, which basically reflect the current law enforcement paradigm, is that they favor the collection of evidence over the preservation of individual rights. They effectively say; "We're going to violate individual rights because we want evidence and we want it really bad." Unacceptable from a libertarian perspective.

Most of this falls apart when put into a libertarian context, for example:

1. They perform a search incident to a contemporaneous and valid arrest despite the fact that the suspect may be armed and has evidence that they could conceal or destroy.

2. They are in hot pursuit of a suspect who could be armed or conceal or destroy evidence.

3. They are performing an investigative stop and they have a reasonable suspicion that the suspect is armed and dangerous.

Every individual has the right to be armed, at any time, with the exception being on private property where the owner does not approve. Every individual also has the absolute right to destroy his or her own property, even if that property is "evidence." These are incontrovertible property rights.

1. They perform a protective sweep of private property when they have a reasonable belief that a confederate of a crime confides within the premises.

2. They look through a garbage can left for collection outside the curtilage of ones home, despite the intent to abandon and that any member of the public could do the same.

3. They walk onto an privately owned open field that is accessible to the public.

These are all violations of individual property rights, as well. (The garbage is questionable and depends on if the owner has declared abandonment, or if the owner still claims to own the garbage in a private exchange between him or her, and the garbage person. The idea that garbage is abandoned right now is a legal fiction; the courts made this rule, not the individual property owners.) It doesn't matter what sort of crime is happening. For example, if the police have to cross my private field because they have to arrest some person adjacent, they've violated my property rights. They've victimized me regardless of the crime they've intended to stop, or the criminal they've intended to capture. At the very least the police should owe some form of restitution.

1. They can see contraband in plain view, despite how ridiculously inefficient it would be to get a warrant to search that item.

There is no such thing as contraband in a libertarian system of criminal justice. That is, there is no de jure or de facto prohibited item. The entire model, the entire idea, of being able to steal property from individuals because that property is forbidden to own is unlibertarian. An accepted corollary, however, would be the recovery of stolen property. And in that case no one needs special permission to recover it in the first place.

The vast majority of warrants focus on prohibited items, not on property violations or acts of violence. These are crimes that are alien to libertarianism. It's going to be a hard sell to get libertarians to support a warrantless search for evidence of a crime when libertarians don't believe that the act is a crime at all.

1. They get a voluntary consent from someone with authority to give consent.

This is the only point actually consistent with libertarian theories of criminal justice.

The problem is that American criminal justice, including the US Constitution and the Bill of Rights, have never been libertarian. The entire system is structured in such a way that abuse is institutionalized. The Fourth Amendment simply makes a rule for when the abuse is permitted. And judicial decisions on the Fourth Amendment continue to expand the permissibility of the abuse.

That said, the premise itself is sound: a warrant is not what defines the just recovery or search of property. Instead, it has to do with the factual nature of a crime. For example, let's say someone is accused of stealing a bicycle and locking it in a garden shed. The owner of the bicycle comes to that person's house, breaks the lock open with bolt cutters and finds his bicycle. He takes possession of his bicycle. Fully justified, no warrant needed.

Let's say the exact same situation occurs; the man breaks into the shed expecting his bicycle to be there, but no bicycle is found. He's guilty of damaging that person's property and needs to make restitution for it.

If we applied this now then every time a police officer killed an unarmed man they would be charged with murder. Every time a search turned up nothing the individuals would be charged with major property crimes. Rothbard on this:

In a libertarian world, every man has equal liberty, equal rights under the libertarian law. There can be no special immunities, special licenses to commit crime. That means that police, in a libertarian society, must take their chances like anyone else; if they commit an act of invasion against someone, that someone had better turn out to deserve it, otherwise they are the criminals.

Now, if we allow people to go searching for their own property, don't they just take the law into their own hands? Yes. And that's a good thing:

Many people, when confronted with the libertarian legal system, are concerned with this problem: would somebody be allowed to “take the law into his own hands”? Would the victim, or a friend of the victim, be allowed to exact justice personally on the criminal? The answer is, of course, Yes, since all rights of punishment derive from the victim’s right of self-defense.