Driving under the influence (DUI) cases in Pennsylvania often begin with a traffic stop. A police officer might pull a car over because they thought the driver was driving suspiciously. A traffic stop for something else, such as speeding or running a stop sign, can lead to a DUI investigation if the officer suspects that the driver is impaired. As long as the officer had a legitimate reason to pull the driver over in the first place, this is not a particularly controversial way for police to enforce Pennsylvania’s DUI laws. A much more controversial method involves DUI checkpoints, where law enforcement can stop vehicles without any particular suspicion. While DUI checkpoints in Pennsylvania are legal, they have to follow strict legal requirements. This blog post will discuss your rights in case you are ever stopped at a DUI checkpoint. A DUI lawyer can help you if you have concerns about a checkpoint.

Know Your Rights Under the Law and the Constitution

The U.S. Constitution protects people from various actions by police and prosecutors. DUI checkpoints are an exception to some of these rights, which is why police have to follow specific procedures when operating them.

The Fourth Amendment to the U.S. Constitution protects people from “unreasonable searches and seizures.” It also requires police to obtain a warrant from a judge before searching a person or their property and before detaining or arresting a person. Article I, § 8 of the Pennsylvania Constitution contains similar language.

The U.S. Supreme Court has identified many exceptions to this requirement over the years. For example, a police officer can pull a driver over — which is a form of “detaining” the driver — if they have “reasonable suspicion” that the driver has violated the law, such as by speeding, running a red light, or driving under the influence of alcohol.

In a DUI case, prosecutors have to show that the officer who pulled the defendant over had reasonable suspicion of something that would justify stopping the defendant’s vehicle. If prosecutors cannot show this, the defense can move to suppress any evidence obtained from the traffic stop, since the stop violated the defendant’s constitutional rights.

Are DUI Checkpoints Legal in Pennsylvania?

A DUI checkpoint involves stopping vehicles with no specific suspicion of DUI or anything else for that matter. Does this mean that checkpoints are “unreasonable seizures” that violate the Fourth Amendment? As long as police officers follow guidelines established by Pennsylvania law, DUI checkpoints are legal.

U.S. Supreme Court

The U.S. Supreme Court decided a case in 1990 called Michigan Dept. of State Police v. Sitz, which involved a Fourth Amendment challenge to DUI checkpoints. The court considered drivers’ interest in not being pulled over by the police without reasonable suspicion of any traffic or criminal offense, and it compared that to the public’s interest in enforcing DUI laws. It found that the public safety function of DUI checkpoints outweighed the Fourth Amendment concerns.

Pennsylvania Law

Title 75, Section 6308(b) of the Pennsylvania Consolidated Statutes allows police to use a “systematic program of checking vehicles or drivers” to enforce DUI laws. Courts have interpreted this to allow DUI checkpoints.

Two decisions by the Pennsylvania Supreme Court, Com. v. Tarbert (1987) and Com. v. Blouse (1992), established guidelines for DUI checkpoints:

  1. Police may only stop a vehicle briefly at a DUI checkpoint.
  2. Police may not search a vehicle stopped at a checkpoint, nor may they search the occupants of a vehicle.
  3. The decision to establish a DUI checkpoint, as well as decisions about location and scheduling, must come from the administrators of a police department, not individual officers.
  4. Police must have objective criteria, developed by police administrators, for deciding which vehicles to stop at a DUI checkpoint. Individual officers should not have discretion as to which cars to stop.
  5. Police administrators should use historical data about DUI incidents to determine where to place checkpoints.
  6. Police must publicly announce the time and location of DUI checkpoints in advance.

How Do DUI Checkpoints Work?

As mentioned above, a DUI checkpoint must be established at a fixed location, meaning that police cannot move the checkpoint without notice to the public. Police must have an objective standard for deciding which vehicles to stop, such as stopping every fifth vehicle that enters the checkpoint. They cannot choose which vehicles to stop based on discriminatory factors like racial profiling.

As a vehicle enters a checkpoint, an officer may direct it to pull over or continue on. If directed to pull over, the driver must do so. An officer may then ask the driver questions directly related to DUI, such as “Have you been drinking tonight?” If the officer has a reasonable basis to suspect that a driver is under the influence of alcohol or drugs, they can send the vehicle to a secondary area for further investigation. If not, they must allow the vehicle to depart.

Additional investigations might include a preliminary breath test to determine blood alcohol content (BAC) or a series of field sobriety tests. Three field sobriety tests are approved for Pennsylvania DUI cases:

  • Walk-and-turn: The driver must walk a straight line, heel-to-toe, for nine steps, then turn around and walk heel-to-toe back to the starting point.
  • One-leg stand: The driver must stand with one foot lifted 6 inches off the ground while they count to 30.
  • Horizontal gaze nystagmus (HGN): The officer moves an object, such as a pen, from side to side in front of the driver, who is instructed to follow it with their eyes, without moving their head. The test is supposed to look for irregular eye movements, which is supposedly a sign of intoxication.

If the officer concludes that the driver is impaired, they may place the driver under arrest. The driver will then be transported to a nearby police station.

What Should I Do If I Get Stopped at a DUI Checkpoint?

If you see a DUI checkpoint ahead of you on the road, you are not obligated to continue to the checkpoint, but this comes with caveats. If you see a checkpoint and turn your vehicle around in a way that violates traffic laws, the police may follow you and pull you over, and they will want to know why you were so eager to avoid the checkpoint. Even if you do not commit any traffic offenses, the police may still follow you.

If you are directed to pull over at a DUI checkpoint, you do not have to provide the police with any information besides your name, along with your license, registration, and proof of insurance. You can refuse field sobriety tests and the preliminary breath test. If you are arrested for suspected DUI, however, you cannot refuse breath testing at the police station.

The state has the burden of proving that the DUI checkpoint was legal. Your DUI lawyer can challenge the checkpoint’s legality by insisting on proof that police complied with all the guidelines established in Tarbert and Blouse. If the police did not follow the law precisely, any evidence they gathered during or after the stop of your vehicle could be thrown out by the judge.

Learn More About Your Rights

If you have questions about a DUI case in Pennsylvania, you should contact a DUI attorney as soon as possible.