The patrol bots were robots created by Blue Sun Corporation during Malcolm Reynolds’ tenure as Sheriff on Deadwood. The robots were created after studying Reynolds, and they had his face and some of his personality. They were intended to aid in law enforcement but were also meant to aid Blue Sun’s desire for more power.
The patrol bots had Mal’s sense of right and wrong, but they were heavy handed and without mercy, enforcing the law regardless of the circumstances. Mal once stopped one from shooting a boy who had been throwing rocks at a building. Mal knew the best action was to call the boy’s mother and talk to her, but the robot only saw a law being broken and intended to shoot the perpetrator.
Mal eventually knew the bots had to be stopped, and he and his crew raided a Blue Sun building to find a device that destroyed all the robots. Blue Sun improved the technology, though and later used it to create the Wash bot.