A Common Driver Habit
Almost all drivers, if not regularly, then from time to time, leave their car’s engine idling—whether out of habit or for convenience. With the arrival of winter in the northern hemisphere, this habit becomes even more widespread, as many start the engine for a long time to warm up the interior before a trip.
A currently little-known law, which has drawn attention in North Carolina, serves as a reminder for many Americans. Leaving a car with the engine running, especially unattended, can lead to a fine in some public places.
What is the “Dawson Rule”
Known in North Carolina as the Dawson Rule, leaving an engine unattended is considered a Class 3 misdemeanor. As one might expect, it is low on the priority list for law enforcement.
It applies only in public areas such as highways, public roads, gas stations, and parking lots. Private property in North Carolina is generally excluded.
Law Enforcement’s Perspective
Onslow County Sheriff Chris Thomas told local station WNCT that enforcing this rule is not exactly a priority, but the logic behind it is still relevant, and not for the reason most drivers expect.
“The law only applies when it’s on a public right-of-way or in an area of public vehicular traffic,” Thomas explained. “Locking and securing your vehicle and turning off the engine is more important to us so the vehicle is not stolen, as it’s often a crime of opportunity.”
This is an interesting nuance. Although the statute itself exists within North Carolina’s efforts to reduce idling and improve air quality, law enforcement tends to view it not so much as an environmental regulation, but as a theft prevention tool.
In practice, officers do not patrol parking lots to issue tickets for idling engines, but they deal with the consequences when unattended cars with running engines disappear.
The Situation in Other States
However, this rule is not unique to North Carolina. 16 states and the District of Columbia have rules regarding unattended idling of one kind or another. Most limit owners to three to five minutes. In some states, like New York, other motorists are encouraged to report violators.
The reminder here is simple. Make sure that wherever you leave your engine running, you do so legally and safely.
Where in the US is Idling Restricted?
The table below lists states and the District of Columbia where similar restrictions are in place.
| State / District | Law’s Scope | Typical Limit |
| Hawaii | Statewide | Varies by situation |
| California | Statewide + local rules | ~5 minutes |
| Arizona | County level (e.g., Maricopa County) | ~5 minutes |
| Connecticut | Statewide | ~3 minutes |
| Colorado | Statewide and local ordinances | Varies |
| Illinois | Statewide on business streets; stricter city rules | Varies |
| Maryland | Statewide | ~5 minutes |
| Massachusetts | Statewide | ~5 minutes |
| Minnesota | City and local ordinances | Varies |
| Nevada | Statewide | ~15 minutes |
| New Hampshire | Statewide with weather exceptions | ~5 minutes |
| New Jersey | Statewide | ~3 minutes |
| New York | Statewide (diesel) + stricter city rules | ~3–5 minutes |
| Pennsylvania | City level (e.g., Philadelphia) | Varies |
| Utah | County and city ordinances | Varies |
| Texas | Local ordinances in urban areas | Varies |
| District of Columbia | District-wide | ~3 minutes |
These diverse approaches across different US regions show that the issue of idling is addressed comprehensively. Although the original reason for introducing such regulations was often environmental—reducing emissions—in practice, they gain an important side effect in the form of crime prevention. This demonstrates how local laws can adapt to current challenges, such as auto theft rates, which are often crimes of opportunity. Drivers, especially during the winter period, should remember not only about comfort but also about the safety of their property and the potential legal consequences, which can vary significantly depending on the state or even the city.