What is one reason why traffic investigators look for vehicle light filaments?

Investigating vehicle light filaments is crucial in understanding the circumstances surrounding a traffic incident. One key reason traffic investigators examine the filaments is to establish whether the vehicle's lights were operational at the time of the crash. By analyzing the filament condition, they can determine if the light was illuminated, which may indicate whether the driver was following traffic laws and using the required lights. This information can be pivotal in reconstructing the events leading up to the accident and understanding factors such as visibility and potential negligence. An operational light is an indication that the driver was likely complying with traffic regulations, while a burned-out filament could suggest otherwise. This analysis provides essential evidence in the investigation process.