Homer appears to be a former prisoner, perhaps from the Ryall State Prison much like Murphy, because of the shackle rings attached to his clothes which bear a striking similarity to Murphy's prison jumpsuit. This is further strengthened by his comments regarding the tunnels. He tells Murphy that one has to be like vermin to survive, then he'd be fine "just like old Homer". One possible escaped prisoner to another, this statement likely gave Murphy a depressing glimpse of what the rest of his future could be reduced to: forgotten, scavenging vagabond, dying alone in the dank underbelly of an unassuming small town.