Driving with no headlights on has led to an impaired driving charge and a separate driving suspension during traffic stops in the past couple days.
The first incident saw city police stop a vehicle Thursday evening after noticing it had no headlights on.
A roadside screening device indicated the driver, a 44-year-old Charlottetown woman, was over the legal limit.
The driver was arrested and transferred to the police headquarters, where breath samples confirmed readings over the legal limit.
The woman will appear in provincial court at a later date to answer impaired driving charges.
Another driver found trouble with the law on Friday when police observed another vehicle operating downtown with no headlights on.
A roadside screening device produced an "alert" reading, which led to a seven-day driving suspension.
The vehicle was towed from the scene.