Al Britton was a sheriff, and the personal friend of a recently deceased man, Frank O'Brien, whose death Sam and Dean were investigating.
History
As Sam and Dean waited in the lobby of the Rock Ridge, CO Sheriff's department, Sheriff Britton appeared and chastised his deputy for keeping federal agents waiting, although he had no problem making them remove their shoes at the door of his office. After a round of hearty handshakes, he lathered on what seemed like a copious amount of hand sanitizer and asked them why they were there.
He seemed taken aback that they were there about Frank O'Brien, telling them that he and Frank had been friends since high school and that they played on the same softball team, the Gamecocks. He said Frank had been acting really jumpy just before he died and had stopped answering his phone. That's why he sent two of his men to his house to check on him; they found his body. Three days later, he was still trying to work up the courage to go see him. He seemed to choke up a bit and brought his hand to his face, then released another torrent of sanitizer.
Further into their investigation, the boys returned to the Sheriff's office to talk to him about the death of Luther Garland. They were misinformed by Deputy Linus that he was out sick. He was in fact holed up in his office, experiencing advanced symptoms of the same strain of ghost sickness that Dean had by then been infected with: extreme paranoia and panic, hallucinations and severely itchy scratches on his arms.
The brothers eventually found out from Luther Garland's brother, John, that Frank O'Brien had brutally murdered Luther, and that Sheriff Britton had allowed him to get away with it.
While Sam and Bobby worked on the plan to vanquish the buruburu responsible for the ghost sickness, Dean was confined to the hotel room, watching the clock.
Sheriff Britton succumbs to ghost sickness.
Sheriff Britton stormed in on him, ranted that he would not be taken down for not busting Frank O'Brien for killing Luther Garland, and drew a gun on him. Dean disarmed him, and during the ensuing struggle Britton clutched his chest and collapsed. He died from a heart attack before Dean could get him to calm down.[1]