The kleptomaniac canine Raffles is a Rottweiler. According to The American Kennel Club, this breed has an inherent desire to protect home and family, and is an intelligent dog of extreme hardness and adaptability with a strong willingness to work, making them especially suited as a companion, guardian and general all-purpose dog.
Apparently, Alex Ball did a bit part as the driving policeman without any record in the final credits. In a career spanning 32 years (1944-1976), he made 191 appearances in films and TV Series, ALL of them uncredited.
Raffles the dog is aptly named inasmuch as it is an homage to the gentleman thief character from the novels and movies featuring him. Raffles the man is a very successful fictional creation of E.W. Hornung, the brother-in-law of Sir Arthur Conan Doyle.