Nevada authorized two kinds of roadblock, and neither is a sobriety checkpoint

Nevada defines its two roadblocks before it authorizes them, and the definitions do most of the work. NRS 484B.007 says an "administrative roadblock" is any structure, device or means used by police "to control all traffic through a point on the highway whereby all vehicles may be slowed or stopped for a lawful purpose other than identifying the occupants of the vehicles or an emergency." NRS 484B.070 says a "temporary roadblock" is a device used to control traffic at a place on a highway "whereby vehicles may be slowed or stopped: 1. To identify the occupants of those vehicles; or 2. Because of the existence of an emergency." The two definitions are mirror images. Identifying occupants is the exclusive province of the temporary roadblock and is expressly excluded from the administrative one.

That matters because the temporary roadblock is the narrower authority. NRS 484B.573(1) permits it only "(a) To apprehend persons known to be wanted for violation of the laws of this State, another state or the United States, and using the highways of this State for the purpose of escape; or (b) To control traffic at or near the scene of a potential or existing emergency or hazard." Paragraph (a) requires that the persons already be known to be wanted, which a suspicionless sobriety screen by definition does not involve, and paragraph (b) is about managing traffic around a crash, a fire or a flood rather than investigating drivers.

The engineering requirements confirm what each device is for. An administrative roadblock under NRS 484B.570(2) must sit at a point clearly visible to approaching traffic at not less than 100 yards in either direction; must carry a sign near the centerline displaying the word "Stop" in letters readable at not less than 50 yards in daytime or darkness; must have at least one red flashing or intermittent light burning at the side of the highway visible at not less than 100 yards; and must be preceded by warning signs telling oncoming traffic that a "police stop" lies ahead, lit by a burning beam light, flare or lantern, placed at least a quarter of a mile out in a rural area and at least 700 feet out in an urban area. A temporary roadblock under NRS 484B.573(2) instead requires a plainly marked authorized emergency vehicle with its warning lights running and at least one flashing red light visible at 100 yards, cones, reflectors or burning flares identifying the entrance, and a further set of devices on both shoulders and near the centerline placed not less than 200 yards and not more than 400 yards from the entrance. These are the specifications of an emergency traffic-control device, not of a screening lane.

NRS 484B.577 preserves the rest of police authority: the provisions of NRS 484B.570 and 484B.573 "do not limit the existing authority of police officers in the performance of their duties involving traffic control." That is a saving clause about traffic control, not a grant of an extra roadblock type, and it does not restore the occupant-identification purpose that NRS 484B.570(1) removed.

An individual impaired-driving stop is unaffected by any of this. A Nevada officer who has reasonable cause to believe a driver committed a civil infraction may halt and detain under NRS 484A.7033(1), may escalate to an investigative detention under NRS 171.123 with its 60-minute ceiling, and may arrest under NRS 171.1231 on probable cause. Impaired driving itself is charged under NRS 484C.110, 484C.120, 484C.130 and 484C.430, and NRS 678D.300(1)(a) confirms that being in actual physical control of a vehicle while under the influence of cannabis is outside the adult-use exemption. Nothing about the roadblock statutes limits an officer who has individualized grounds.

One more roadblock rule exists and it is about water, not alcohol. NRS 484B.574 makes a driver who unlawfully travels through a temporary roadblock set up because of flooding or water on the roadway liable for the expenses of the emergency response needed to pull the occupants or the vehicle out, capped at $2,000 for a single incident, with immunity for someone who did it in a good faith effort to assist a person in danger.

Running a roadblock in Nevada is a serious offense even though the roadblocks themselves are limited. NRS 484B.580(1) makes it unlawful to proceed or travel through an administrative or temporary roadblock "without subjecting himself or herself to the traffic control established at the roadblock," and separately unlawful to disobey the lawful orders or directions of a police officer at one. Subsection 2 sets the penalty: if the person is the direct cause of a death, of substantial bodily harm to any person, or of property damage over $1,000, it is a category B felony punishable by 1 to 6 years in state prison, a fine of up to $5,000, or both. If none of those results, it is a gross misdemeanor.

Where the temporary roadblock was set up because of flooding or water on the roadway, NRS 484B.574 adds civil liability on top of the criminal penalty. The driver owes the expenses of any emergency response required to remove the driver or a passenger from the vehicle, or to move a vehicle that becomes inoperable, including salaries and wages, deemed wages of volunteers and fuel and equipment costs, but excluding air ambulance and ambulance charges under NRS 450B.030 and 450B.040. Liability is capped at $2,000 for a single incident, an insurance policy may exclude coverage for it, and the charge is a debt collectable proportionately by the entities that incurred the expenses.