Velvet Lies — L. Shelby

"You mean the man's own servants won't say who killed him because it wouldn't be polite?"

Zelli thought he was just supposed to be carrying diplomatic messages from his home country to the Imperial Court of Borgim. But when he arrives at the Coral Palace, he discovers that the ambassador is suspected of murder. The Emperor assigns Zelli to the case, and gives him just two days to find the true culprit. It sounds like an easy task; there were half a dozen witnesses. Too bad the rules of etiquette absolutely forbid anyone from admitting that a member of the Imperial Court might do something wrong. How will Zelli find the murderer, when no one will tell him the truth?