A friend of mine asked me to comment on this. I wrote the following:

My perspective is that such tests constitute a search and should require a warrant. If you look at the story, the people running this program agree - the story dances around that a bit. They say:

The nation's highest court ruled in 1966 that police could have blood tests forcibly done on a drunk driving suspect without a warrant, as long as the draw was based on a reasonable suspicion that a suspect was intoxicated, that it was done after an arrest and carried out in a medically approved manner.

That ruling basically has nothing to do with this story. The after arrest part is key - if you've already been arrested the constitutional issues are not the same. You are a prisoner. Later down in the article they say:

Under the state's implied consent law, drivers who refuse to voluntarily submit to the test lose their license for a year, so most comply. For the approximately 5 percent who refuse, the officer obtains a search warrant from an on-call judge and the suspect can be restrained if needed to obtain a sample, Layden said.

So, a warrant is required. However, "we pulled the guy over because he was weaving" is probable cause sufficient to get a warrant, so it doesn't really matter.

So, the question really boils down to what you think about "implied consent." If they had absolutely no basis to suspect you of being intoxicated they couldn't get a warrant, but you'd still loose your license.

I'm not sure I'm comfortable with the idea of "implied consent" when it comes to the fourth amendment. It goes to show you how little respect the fourth amendment has when the game for legislators is to come up with a creative way of thinking it out of existence.

Imagine you started a neighborhood, and you wanted it to be crime free. You create an Home Owners Association with an HOA contract. In that contact you include language that says that if you buy a home in this neighborhood you consent to suspicionless searches of your home and property by the police. Its buried in the fine print - most people don't really notice its there and the police rarely exercise this power anyway so its not a practical concern, until it is. Here consent is more than implied - you actually signed paperwork authorizing searches of your property.

If this practice became common, over time it might be harder and harder to buy a home in a "nice" neighborhood without signing your constitutional rights away.

Now, imagine you started an ISP, and you wanted it to be crime free...

This is the future.

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