You might see this listed on a traffic ticket, crash report, insurance letter, or hear an officer say a driver "failed to stop for a steady red signal." That means a driver entered an intersection after the traffic light had turned red, instead of stopping before the marked line, crosswalk, or intersection when required.

At a general level, it is a moving traffic violation based on ignoring a traffic control signal. The exact facts can matter. A driver may still be allowed to turn right on red after stopping first, unless a sign prohibits it. But driving straight through a red light, or making a turn without first stopping when the signal requires it, can lead to a citation and may be used as evidence of negligence if a collision follows.

For an injury claim, running a red light often becomes a key question in proving fault. Police observations, traffic camera footage, witness statements, skid marks, and vehicle damage patterns may all be used to show who had the right of way. In Montana, traffic signals are governed by Montana Code Annotated § 61-8-209 (2023), which sets out drivers' duties at steady red, yellow, and green lights.

That can directly affect compensation for medical bills, lost income, and pain and suffering. In poor visibility, including wildfire smoke that can reduce sight distance on highways near Bozeman and elsewhere, a driver may argue conditions were difficult, but that usually does not excuse failing to obey a red signal.