Situation…
It was claimed by the occupant that she had put out a fire after seeing a bright light in the area around the letterbox. On investigation, it was found that a curtain, of thin polyester/cotton material, had been suspended on a rail behind the front door to act as a draught barrier.
It was suggested that the occupant lit the curtain and allowed it to burn beyond the letterbox before pulling it down and putting the fire out. Motives considered were to either self-harm or convince the police of the existence of harassment.
Action…
The Prosecution had produced a credible explanation.
However, we were able to offer a second explanation.
Tests confirmed that it is virtually impossible to light a match or cigarette lighter through a conventionally sprung letterbox: it requires the ability to hold both flaps permanently open (using at least one hand), pass the other hand, and lower arm entirely through a narrow letterbox, holding the match/lighter and then ignite it. It is possible to pass a gas-powered lighting wand through a letter-box, using the strength of the metal wand to push, hold, open the inside flap, and then ignite the lighter. Tests showed that the wand could be pushed through a sufficient distance for the flame to contact the curtain, which would rapidly ignite and burn up from the point of ignition, melting the plastic flap as it progressed.
Result…
This mechanism was offered as an additional credible explanation, and accepted as such by the Prosecution. Faced with two possible explanations, the case was not proceeded with.