The Nevada Supreme Court has held a  obstruction of a police officer statute unconstitutional when applied to the following situation

At approximately 4:15 a.m., a Carson City sheriffs deputy pulled over a vehicle for running a stop sign. The vehicle had three occupants. When questioning the driver, the deputy smelled alcohol coming from the vehicle. The deputy asked the driver if he would submit to a voluntary field sobriety test. Before the driver could answer, petitioner William Scott, who was a passenger in the vehicle, interrupted the deputy. The deputy continued to question the driver, and according to the deputy, Scott interrupted him a second time and told the driver not to do anything the deputy said. Scott allegedly went on to state “that his dad [was] a lawyer and he knows all about the law.” After the second interruption, the deputy threatened Scott with arrest “for obstructing and delaying a peace officer” if he did not remain quiet.

After a third interruption, the deputy ordered Scott out of the vehicle. The deputy arrested Scott and called for backup. Scott cooperated during the arrest. A second deputy transported Scott to jail, and the first deputy resumed his DUI investigation of the driver.

The majority

CCMC 8.04.050(1) is unconstitutionally overbroad because it “is not narrowly tailored to prohibit only disorderly conduct or fighting words.” Hill, 482 U.S. at 465. CCMC 8.04.050(1) is unconstitutionally vague because it lacks sufficient guidelines and gives the sheriff too much discretion in its enforcement. Accordingly, we grant Scott’s petition and direct the clerk of this court to issue a writ of certiorari instructing the district court to vacate its order denying Scott’s appeal. We further remand to the district court with instructions to enter an order reversing Scott’s conviction in part on the grounds that CCMC 8.04.050(1) is unconstitutional on its face and to determine whether Scott may properly be charged under the remainder of CC MA G, .050.

There is a concurring/dissenting opinion. (Mike Frisch)