North Carolina Checking Stations and Roadblocks: How DUI Checkpoints Operate Under G.S. 20-16.3A

DUI checkpoints ordinarily involve standardized patterns for stopping vehicles, as well as the use of portable breath tests (PBTs) and SFSTs – Standardized Field Sobriety Tests to assess possible alcohol consumption and appreciable impairment. North Carolina law allows law enforcement agencies to set up checking stations and roadblocks pursuant to N.C.G.S. 20-16.3A to check for things like license violations and to enforce the “drunk driving” (impaired driving) laws. The process must follow certain constitutional and statutory guidelines to avoid arbitrary or discriminatory stops.

The following content is a general overview of how roadblocks and checking stations work, including the difference between a brief roadside stop and a more formal implied-consent procedure. If you have questions about a checkpoint stop in North Carolina—or wish to talk about a specific legal concern related to N.CG.S. 20-16.3A—call or text the Powers Law Firm at 704-342-4357, or email Bill Powers at Bill@CarolinaAttorneys.com.

The Statutory Basis for DUI Checkpoints: N.C.G.S. 20-16.3A

G.S. 20-16.3A authorizes law enforcement to conduct checking stations for confirm compliance with the Chapter 20 Motor Vehicle laws. Officers may set up a roadblock (also sometimes referred to as checking stations or “dui checkpoints”) to monitor compliance with the traffic laws, screen for license infractions, and detect possible impairment. The statute states:

“A law‑enforcement agency may conduct checking stations to determine compliance with the provisions of this Chapter.”

The statute clarifies that agencies must predesignate a pattern for stopping vehicles, and officers are not permitted to pick cars randomly at their personal, subjective discretion. This requirement is intended to reduce arbitrary stops, profiling, and other unconstitutional police action. Checking stations under G.S. 20-16.3A are generally seen in contexts such as:

DWI or License Checkpoints: Officers systematically stop vehicles to see if drivers have valid licenses, registration, or if they exhibit signs of impairment.
Safety Checks: Agencies may also confirm seat belt usage, ensure children are in proper car seats, or verify insurance compliance.

Courts have recognized that checkpoints and the related stops are generally minimal intrusions if set up according to a neutral plan. Random or undocumented patterns can raise constitutional and statutory issues. It’s important to note, roadblocks and DUI checkpoints are an important and sometimes troubling exception to important Fourth Amendment rights relating to traffic stops.

Constitutional Considerations: The Fourth Amendment

While G.S. 20-16.3A provides statutory authority, the Fourth Amendment to the United States Constitution remains applicable. A checkpoint or roadblock is a form of seizure. However, Michigan Dept. of State Police v. Sitz held that sobriety checkpoints are permissible when executed under objective guidelines and established for a legitimate purpose, including promoting public safety. North Carolina courts have interpreted the stop and seizure laws similarly, requiring law enforcement agencies to establish a legitimate primary programmatic purpose and not allow individual officers unfettered freedom to stop certain drivers and let others pass.

Reasonable Suspicion vs. Pattern
For a typical traffic stop, an officer needs reasonable suspicion or probable cause that a driver violated a law. At a checkpoint, the officer can lawfully stop cars according to a predetermined pattern (e.g., every fifth vehicle) without individual suspicion.
Neutrality and No Unchecked Discretion
If an officer deviates from the plan—like deciding to stop every sports car on a whim—courts might declare the stop unconstitutional. Agencies must show they followed the official policy to prevent arbitrary enforcement or discriminatory effect.

Because these operations are deemed “limited intrusions” on the freedom to be left alone, the courts balance the governmental interest in roadway safety with the purported minimal inconvenience to drivers. Still, a motorist who believes the plan was not followed may contest the stop’s legality.

Written Policies and the Need for a Pre-Approved Pattern

N.C.G.S. 20-16.3A(a1) sets forth that law enforcement agencies conducting checking stations must:

Designate a pattern in advance for stopping vehicles.
Develop or adopt a written policy that sets out how the pattern works (for example, stopping every car, every third car, or using a randomizer that does not rely on officer impulse).
Ensure no officer wields unchecked discretion to select which driver is stopped.

The policy need not be extremely detailed, but it should outline a clear plan. If traffic or safety concerns require changing the pattern mid-operation, the new approach must be explained in the plan (i.e., a contingency) such as shifting from stopping every fifth car to every third car due to traffic volume or allowing a certain number vehicles to pass through to avoid traffic congestion. Such contingencies should be established in advance, as part of developing a DUI checkpoint plan (checking station / roadblock) to avoid the appearance of subjective, unconstitutional officer-driven decisions. Click here for more information regarding the historical significance of checkpoints, probable cause, and NC DWI Search and Seizure.

Agencies often keep a written statement of the primary programmatic purpose, such as targeting DWI offenses or license infractions. A legitimate programmatic purpose may prevent claims of a purely arbitrary dragnet. If a court finds the agency set up the station solely to fish for unrelated offenses, the checkpoint may face scrutiny and possibly serve as a motion to suppress and/or motion to dismiss for lack of evidence.

Administering a PBT – Portable Breath Test at a Checkpoint

During a checkpoint, officers may ask drivers for a license, registration, and proof of insurance. If an officer notices signs of alcohol—like an odor or open containers—the officer can request that the driver submit to a portable breath test (PBT) under N.C.G.S. 20-16.3. That statute outlines when an officer may use a screening device. In particular:

Reasonable Suspicion: If the officer detects evidence suggesting the driver consumed alcohol and has committed an implied consent offense, the officer can ask for a PBT.
Not an Arrest: Requesting a PBT under G.S. 20-16.3 is not the same as arresting the driver. It is a preliminary step to see if further investigation is warranted.
Approved Device: The device itself must be on North Carolina’s approved list of PBT devices, and the officer must comply with calibration and administration protocols.

If the driver’s reading suggests consumption of alcohol and/or other impairing substances, the officer may investigate further, including requesting standardized field sobriety tests (SFSTs) and making further inquiry into the driver’s statements about prior drinking. If the driver refuses the PBT, the officer is directed to consider that refusal as one factor in deciding if probable cause exists for arrest. The specific language in the statute utilizes the term of mandamus “shall.” However, refusal of a PBT is not an implied-consent refusal. As such, refusing the PBT in North Carolina does not prompt immediate license revocation as a willful refusal.

Balancing a Brief Roadside Stop and Fourth Amendment Rights

The courts permit brief seizures at checkpoints but remain cautious of extended detentions. (See State v. Mitchell) Once a driver’s license and registration are checked, and if there are no signs of wrongdoing, the driver should be allowed to proceed. The Fourth Amendment and Article I, Section 20 of the North Carolina Constitution limit the scope of questioning and the length of time the driver is held at the checkpoint.

Key Points:

The officer may expand the duration of the detention if probable cause or reasonable suspicion arises. For example, slurred speech, an odor of alcohol, or evasive answers may justify further inquiry.
If the officer sees no signs of impairment or violations of the law, the driver should be released promptly, without further intrusion or incident.
Searching the vehicle or driver beyond the checkpoint’s stated purpose may require additional suspicion or consent, depending on the specific fact pattern involved.

Courts examine how long each stop lasts and whether the actual procedure implemented by law enforcement matches the stated pattern and primary programmatic purpose. Significant deviations from the checkpoint plan without explanation and proper purpose may undermine the legality of the checkpoint as applied to an individual motorist and subject the purportedly unintrusive, brief investigatory detention to further scrutiny.

Improperly Conducted Checkpoints: Possible Defense Strategies

If an agency sets up a checkpoint without a valid purpose or fails to follow the plan, a driver stopped at that location might, in appropriate legal and factual circumstances, file a motion to suppress evidence gained from the stop.

No Written Policy: If the agency lacked any written pattern or changed it at random, the stop might not be valid. It’s important to note, while a best practice, written DUI checkpoint plans are not required in every instance.
Officer’s Discretion: The officer singled out certain vehicles for no stated reason, possibly violating the neutral plan and primary programmatic purpose.
Extended Detention: The driver was kept at the checkpoint longer than necessary, going beyond what may be deemed a minimal intrusion.
No Programmatic Purpose: The station did not serve a recognized, legitimate state interest, such as DWI detection or license checks, possibly raising constitutional concerns.

Roadblocks and checkpoints used as a pretext to search vehicles for contraband or other unlawful purpose(s), could be deemed both unconstitutional(and contrary to the North Carolina General Statutes regarding checking stations. If the basis of the stop is deemed invalid by a court of competent jurisdiction, evidence thereafter obtained during that detention could be suppressed. Each case is different. That’s one reason it makes sense to consult with an experienced DUI defense lawyer about the specifics of your legal matter.

N.C.G.S. 20-16.2 and Implied-Consent Testing at a Checkpoint

North Carolina General Statute § 20-16.2 addresses implied-consent testing, typically after an officer arrests a driver for impaired driving or a similar offense. At a checkpoint, an officer who has reasonable grounds (probable cause) to make an arrest can then request an evidentiary breath test back at the station using the Intox EC/IR II machine. This is distinct from the roadside PBT:

PBT: Preliminary Breath Test (a type of alcohol screening device). The numeric reading is generally not introduced in court to prove exact BAC as substantive evidence of impairment in North Carolina.
Implied-Consent Breath Test: Administered on a machine approved for evidentiary use, with the driver given statutory rights (to contact a witness, wait up to 30 minutes, etc.).

Once the driver is placed under arrest, the implied-consent procedures govern how the State obtains a more definitive result. An arrest for DWI in North Carolina also affords the accused additional rights, including an Implied Consent Offense Notice. While a checkpoint provides the setting for the initial vehicle stop, the ultimate DWI prosecution typically relies on a formal breath test or blood draw and not the PBT alone.

Review of Checking Stations: Analyzing the Metrics

Some agencies keep logs or after-action reports documenting how the checkpoint was established:

Location and Duration: Officers note the start time, end time, and precise location.
Pattern of Stops: The plan might specify stopping every vehicle or every third car, with notes if it changes mid-operation due to traffic backups or safety concerns.
Tracking Metrics: Post roadblock and checkpoint summaries often include how many citations were issued, the type of offense, and whether any drivers were arrested for DWI.

While there is no single statewide requirement for how detailed these logs must be, agencies usually maintain them as standard procedure and as part of the North Carolina Governor’s Highway Safety Program BAT Mobile Campaign. If a DUI defense lawyer challenges the checkpoint’s legitimacy, such records may show compliance with G.S. 20-16.3A and the goals of the primary programmatic purpose were met. In contrast, missing or vague reports might call into question the efficacy of the checking station and/or legitimacy of the purported public safety concern at issue.

Practical Tips for Roadblocks: What to do if you’re stopped at a DUI Checkpoint

Stay Calm and Follow Directives: Drivers are typically required to present a valid license and proof of insurance or vehicle registration. Motorists are not required to answer questions or provide information to law enforcement officers.
Short Detention: If the officer sees no evidence of impairment or violations, the driver should be allowed to continue without further hindrance.
If the Officer Suspects Impairment: The officer may request a PBT consistent with N.C.G.S. § 20-16.3. If the driver shows signs of appreciable impairment, further testing using SFST – Standardized Field Sobriety Tests and arrest could follow.
Refusal of PBT: Declining the roadside screening does not cause an immediate license revocation as a “willful refusal,” but the officer is required to consider unwillingness to submit to PBT testing as part of the arrest decision and probable cause to arrest for impaired driving.
Contact Counsel: If you were arrested or cited at a DUI checkpoint, immediately consulting with a defense lawyer can help address any looming license suspension deadlines, examine whether a civil revocation may be challenged, and determine if you qualify for a pretrial limited driving privilege. Legal guidance early on in the process also allows time to plan a defense strategy, gather important arrest documentation (including BWC – Body Worn Camera evidence, if any) and assess whether the checkpoint followed the relevant statutory laws and Constitutional Rights.

DUI Defense Lawyers: Powers Law Firm

Checking stations and roadblocks can play a role in discovering possible license violations or signs of impairment, but they should follow G.S. 20-16.3A and relevant constitutional principles. Best practices for a DUI checkpoint include a written plan, a neutral stopping pattern, and minimal officer discretion.

If you have questions about a checkpoint stop or face a DWI charge in Charlotte, Monroe NC, Iredell County, Gaston, Rowan, or Union County NC after a North Carolina roadblock, the legal team at the Powers Law Firm is available for consultation. Call or text 704-342-4357 or email Bill Powers at Bill@CarolinaAttorneys.com. Understanding the rules behind checking stations, PBT tests, and the implied consent law can help clarify whether law enforcement complied with the NC DWI laws and honored your Constitutional rights.