Only one breed standard we know of includes a call for an expression that is “essentially scowling.”  From the Chow Chow breed standard: “Expression essentially scowling, dignified, lordly, discerning, sober and snobbish, one of independence. The scowl is achieved by a marked brow with a padded button of skin just above the inner, upper corner of each eye; by sufficient play of skin to form frowning brows and a distinct furrow between the eyes beginning at the base of the muzzle and extending up the forehead; by the correct eye shape and placement and by the correct ear shape, carriage and placement.”