"Gold dragons are the most powerful of the metallic dragons, and the most dedicated to defeating evil. They spend the bulk of their lives in human form, seeking out evil and punishing wrongdoers to the best of its considerable abilities. Its typical mode of operation runs roughly along the lines of a sting operation: the dragon will listen for stories of dangerous or evil creatures or persons, then reveals its true form and metes out punishment. They prefer to turn villains over to law enforcement if available, but will ultimately take whatever actions they deem necessary in order to see justice served. They are best summarized as the paladins of the draconic world."
-Forgotten Realms Wiki