Can an investigator prove that a cigarette started a car fire?

Question

The whole car burnt down, my husband swears a car passing by threw a cigarette out and he thinks thats what started it, can it be proven???

Answer 1

Fire inspectors can usually sort out within a reasonable certainty what caused a fire, where it started, and how it spread. Your insurance company will probably pay for the investigation. Not to cast undue aspersions, but it sort of sounds like he torched it.

Modern car upholstery is very flame-retardant, so it's a surprise to hear that a single burning cigarette could take out a car. Back when I used to smoke, I once had a cigarette burn in the back seat for nearly ten minutes until I could get off the highway and stop to dispose of it, and it only left a small black circle. (Car is ten years old.)