Sheriff Gerald Couch doesn’t come from a family legacy of law enforcement, although a fictional law enforcement legend is perched on his office shelf. “That’s one of my prized possessions,” he said, eyeing a signed picture of the cast of “The Andy Griffith Show.” The portrait of Andy Griffith, Don Knotts and others sits among the books, certifications and accolades that line Couch’s newly inhabited office at the Hall County Sheriff’s Office.