Traffic stops require reasonable suspicion to pull over your car under the Fourth Amendment. I find it hard to explain how a DUI checkpoint is not a similar action to a traffic stop.
The Supreme Court has made bad rulings - we're certainly lucky Dred Scott v. Sandford doesn't still apply - and a 6-3 split indicates some significant disagreement even among the foremost legal minds in the country.
From a common-sense standpoint, I don't see how a DUI checkpoint isn't fundamentally similar to a traffic stop, regardless of the SCOTUS decision that permits them.
>Thank god one's civil liberties aren't dependent on whether or not you are convinced by them.
Apparently they are dependent on whether SCOTUS is convinced.
A DUI checkpoint is fundamentally different because police are unable to discriminate who they stop. They stop everyone who passes through the checkpoint.
The harm DUI stops try to reduce are far more imminent than regular traffic stops. Drunk driving is far more dangerous than a broken tail light. That difference matters.