Tonight's DUI checkpoint will be located in the 7600 block of Colerain Avenue (US-27), and will be in operation from 9:30 PM to 1:30 AM.

Because the Supreme Court said so, thats why.  No really, the constitutionality of DUI Checkpoints was challenged in a Michigan case called Michigan Dept. of State Police v. Sitz.   Basically, the Supreme Court decided the infringement upon a driver who is stopped at a checkpoint is not as important as the Government's goal in stopping Drunk Drivers.

The Chief Justice in that case stated:

Although not a probable cause case, DUI Checkpoints deal with a whole host of Constitutional Issues.  Regardless, the Hamilton County OVI Task Force has announced the will be operating a DUI Checkpoint this Friday Night somewhere in Hamilton County.  They typically do not release the exact location until the morning of the checkpoint.

DUI checkpoint tonight in Butler County on Muhlhauser Road at Inter-Ocean Drive, west of Ohio 747 near Fairfield.   

Probable Cause or a Police Officer's lack thereof is attacked during a Motion to Suppress hearing.  If the Judge finds that a Police Officer lacked probable cause to stop your vehicle, all evidence after the stop is suppressed or thrown out.   What does this mean?  For example, lets say you are stopped because a police officer said you were traveling below the posted speed limit.  This is not a violation of the law!  Your attorney files a motion to suppress and the Judge holds a hearing.  After the hearing the Judge decides that the police officer should not have been able to stop you.  So even though you blew a .184 on the breathalyzer and admitted to being drunk, all of this evidence is suppressed or thrown out.  Meaning the government can't go forward and you win!

I can't say it enough...any violation of the law is enough to get you pulled over.  In Virginia, your air fresheners must conform to a certain size.  The police saw an oversized air freshener hanging from a defendant's mirror and pulled him over.  Of course he had drugs in the car, but that is besides the point. 
 

A Court in Pennsylvania upheld a man's conviction for a DUI after finding the police officer had probable cause to stop a vehicle for littering. 

Again, any violation of the law no matter how insignificant can give a police officer probable cause to stop your car. 

This is a great case out of Fairfield County.  Basically, a police officer stopped a car because he heard the Defendant rev his engine and it appeared as though he was traveling faster than the posted speed limit.  Thankfully, the Court of Appeals held that the police officer did not have probable cause to stop the car and threw the case out.

Below is a case out of Columbus, Ohio where a person was stopped for just having a license plate light burnt out.  Make sure your license plate light is working, if not you could end up with a DUI.