there was evidence of gasoline on the wood floor. >> and the single biggest piece of evidence for them to conclude this was an arson fire was the finding of gasoline in the hardwood floor, because how else would you explain gasoline in a living room? >> when the test results come back, it changes from i don't know to, wow, we have an accelerant here, this must be an arson, and that changes people's opinions. >> to prosecutors, the presence of gasoline meant murder. based on this evidence, prosecutors believe that paul poured gasoline on the living room floor while his parents were upstairs asleep. he then set the room on fire and called the fire department. the heat and smoke made it impossible for paul's parents to make it out of the house alive.