Running a red light is illegal in all states and a ticket or citation for the infraction or offense may lead to a significant fine, demerit points on a driver’s license or driving record, and increased insurance premiums (upon conviction, guilty plea, or plea of no contest).

Due to limited resources many states use automated red-light cameras—also known as photo enforcement—to take a digital photograph of a vehicle (and its license plate) that violates the red light or traffic signal by entering the intersection and failing to stop after the light has turned red. The use of red-light cameras to issue traffic tickets or citations (mailed to the driver) has been controversial, with claims that it violates Constitutional rights.

Laws vary from state to state and in some states red-light cameras are a permitted enforcement tool; in some states they are prohibited; and in some states they are prohibited unless permitted by a local ordinance (city or town).

In Illinois, running a red light is considered a traffic violation and is illegal under state law. Violators can face fines, points on their driving record, and potentially higher insurance rates. Illinois permits the use of automated red-light cameras as an enforcement tool to capture digital photographs of vehicles that run red lights. These cameras are typically installed at intersections with high incidences of traffic violations and accidents. The registered owner of the vehicle receives the citation in the mail. The use of red-light cameras in Illinois has been subject to debate, with some arguing that it infringes on constitutional rights. However, the state has established regulations for the implementation of these systems, and they are widely used in various municipalities, including Chicago. It's important for drivers to be aware of and comply with traffic signals and the specific regulations regarding red-light cameras in the municipalities they drive through.