murder_opinion_effect

murder_opinion_effect = {
	$VICTIM$ = {
		#Victim's family
		every_spouse = {
			limit = { NOT = { this = $MURDERER$ } }
			add_to_temporary_list = close_family_murder_opinion_list
		}
		every_close_family_member = {
			limit = { NOT = { this = $MURDERER$ } }
			add_to_temporary_list = close_family_murder_opinion_list
		}

		if = {
			limit = {
				any_in_list = {
					list = close_family_murder_opinion_list
					always = yes
				}
			}
			every_in_list = {
				list = close_family_murder_opinion_list
				custom = all_close_family_and_spouses

				add_opinion = {
					target = $MURDERER$
					modifier = murdered_close_family_crime
				}
			}
		}
		#Victim's friends and lovers
		every_relation = {
			type = friend
			limit = {
				NOR = {
					this = $MURDERER$
					this = $VICTIM$
					is_in_list = close_family_murder_opinion_list
				}
			}
			add_to_list = victim_close_relations_list
		}
		every_relation = {
			type = lover
			limit = {
				NOR = {
					this = $MURDERER$
					this = $VICTIM$
					is_in_list = close_family_murder_opinion_list
					is_in_list = victim_close_relations_list
				}
			}
			add_to_list = victim_close_relations_list
		}
		if = {
			limit = {
				any_in_list = {
					list = victim_close_relations_list
					always = yes
				}
			}
			every_in_list = {
				list = victim_close_relations_list
				custom = all_friends_and_lovers
				add_opinion = {
					target = $MURDERER$
					modifier = executed_close_relation_opinion
				}
			}
		}
	}
}

As written in game/common/scripted_effects/00_murder_effects.txt.