A really stupid question SPOILER
Why would Mr. Jernigan sit down in a metal chair, outside in the winter, while they were trying to get into the house? I mean, that chair must have been freezing cold. I know, if he had not sat down, he would not have gotten electrocuted. It just seems to me, there was no reason for him to sit down there and then.
Or did he say to himself: "I think I'll just have a rest in this freezing chair"?