portrait_imperial_trigger

portrait_imperial_trigger = {
	trigger_if = {
		limit = { exists = this } # To check if this is an actual character
		OR = {
			# Rulers
			AND = {
				is_governor = no
				tgp_portrait_liege_or_ceremonial_liege_emperor_trigger = yes
				NOR = {
					AND = {
						government_has_flag = government_is_republic
						primary_title.tier > tier_barony
					}
					AND = {
						is_ruler = yes
						government_has_flag = government_is_theocracy
					}
				}
				portrait_$CULTURE_INPUT$_clothing_trigger = yes
			}
			# Spouses
			AND = {
				exists = primary_spouse
				OR = {
					is_ruler = no
					highest_held_title_tier <= primary_spouse.highest_held_title_tier
				}
				primary_spouse = {
					is_governor = no
					tgp_portrait_liege_or_ceremonial_liege_emperor_trigger = yes
					NOR = {
						AND = {
							government_has_flag = government_is_republic
							primary_title.tier > tier_barony
						}
						AND = {
							is_ruler = yes
							government_has_flag = government_is_theocracy
						}
					}
					portrait_$CULTURE_INPUT$_clothing_spouse_trigger = yes
				}
			}
		}
	}
	trigger_else = {
		scope:highest_held_title_tier >= tier_empire
		portrait_$CULTURE_INPUT$_clothing_trigger = yes
	}
}

As written in game/common/scripted_triggers/00_clothing_triggers.txt.