Besides which, "Bard" would usually be "バード" in katakana. I'm strongly against translating it as "Bald." Probably "Vald" would be the closest reasonable match, but it still seems a bit awkward.
There's nothing particularly official about it. Those conventions are for a style of mystery novel that was most popular in the early 20th century and there's no rule that all mystery or mystery-related novels must fall into that subgenre. Notably, police procedurals can be both extremely...