diff --git a/src/game_actor.cpp b/src/game_actor.cpp
index 5f4ee62932..d9483da399 100644
--- a/src/game_actor.cpp
+++ b/src/game_actor.cpp
@@ -84,7 +84,7 @@ int Game_Actor::GetId() const {
 	return actor_id;
 }
 
-bool Game_Actor::UseItem(int item_id) {
+bool Game_Actor::UseItem(int item_id, const Game_Battler* source) {
 	const RPG::Item* item = ReaderUtil::GetElement(Data::items, item_id);
 	if (!item) {
 		Output::Warning("UseItem: Can't use invalid item %d", item_id);
@@ -110,7 +110,7 @@ bool Game_Actor::UseItem(int item_id) {
 		return true;
 	}
 
-	return Game_Battler::UseItem(item_id);
+	return Game_Battler::UseItem(item_id, source);
 }
 
 bool Game_Actor::IsItemUsable(int item_id) const {
diff --git a/src/game_actor.h b/src/game_actor.h
index 3695af3c43..e2dd5929a3 100644
--- a/src/game_actor.h
+++ b/src/game_actor.h
@@ -73,7 +73,7 @@ class Game_Actor : public Game_Battler {
 	 * @param item_id ID if item to use
 	 * @return true if item affected anything
 	 */
-	bool UseItem(int item_id) override;
+	bool UseItem(int item_id, const Game_Battler* source) override;
 
 	/**
 	 * Checks if the actor is permitted to use the item at all.
diff --git a/src/game_battler.cpp b/src/game_battler.cpp
index 9aae16625f..a3a5473ea2 100644
--- a/src/game_battler.cpp
+++ b/src/game_battler.cpp
@@ -233,7 +233,7 @@ bool Game_Battler::IsSkillUsable(int skill_id) const {
 	return true;
 }
 
-bool Game_Battler::UseItem(int item_id) {
+bool Game_Battler::UseItem(int item_id, const Game_Battler* source) {
 	const RPG::Item* item = ReaderUtil::GetElement(Data::items, item_id);
 	if (!item) {
 		Output::Warning("UseItem: Can't use item with invalid ID %d", item_id);
@@ -282,7 +282,7 @@ bool Game_Battler::UseItem(int item_id) {
 		return true;
 	}
 
-	bool do_skill = RPG::Item::Type_special
+	bool do_skill = (item->type == RPG::Item::Type_special)
 		|| (item->use_skill && (
 				item->type == RPG::Item::Type_weapon
 				|| item->type == RPG::Item::Type_shield
@@ -294,19 +294,17 @@ bool Game_Battler::UseItem(int item_id) {
 
 	if (do_skill) {
 		auto* skill = ReaderUtil::GetElement(Data::skills, item->skill_id);
-		if (skill != nullptr) {
-			Game_Battler* source = this;
-			if (skill->scope != RPG::Skill::Scope_self) {
-				source = Main_Data::game_party->GetHighestLeveledActorWhoCanAct();
-			}
-			UseSkill(item->skill_id, source);
+		if (skill == nullptr) {
+			Output::Warning("UseItem: Can't use item %d skill with invalid ID %d", item->ID, item->skill_id);
+			return false;
 		}
+		UseSkill(item->skill_id, source);
 	}
 
 	return false;
 }
 
-bool Game_Battler::UseSkill(int skill_id, Game_Battler* source) {
+bool Game_Battler::UseSkill(int skill_id, const Game_Battler* source) {
 	const RPG::Skill* skill = ReaderUtil::GetElement(Data::skills, skill_id);
 	if (!skill) {
 		Output::Warning("UseSkill: Can't use skill with invalid ID %d", skill_id);
diff --git a/src/game_battler.h b/src/game_battler.h
index 5b9cca4a19..c37271e5e1 100644
--- a/src/game_battler.h
+++ b/src/game_battler.h
@@ -352,7 +352,7 @@ class Game_Battler {
 	 * @param item_id ID if item to use
 	 * @return true if item affected anything
 	 */
-	virtual bool UseItem(int item_id);
+	virtual bool UseItem(int item_id, const Game_Battler* source);
 
 	/**
 	 * Applies the effects of a skill.
@@ -364,7 +364,7 @@ class Game_Battler {
 	 * @param source battler who threw the skill
 	 * @return true if skill affected anything
 	 */
-	virtual bool UseSkill(int skill_id, Game_Battler* source);
+	virtual bool UseSkill(int skill_id, const Game_Battler* source);
 
 	/**
 	 * Calculates the Skill costs including all modifiers.
diff --git a/src/game_party.cpp b/src/game_party.cpp
index 55bbd984ce..effe066f1a 100644
--- a/src/game_party.cpp
+++ b/src/game_party.cpp
@@ -218,34 +218,36 @@ bool Game_Party::IsItemUsable(int item_id, const Game_Actor* target) const {
 		return false;
 	}
 
-	if (item_id > 0 && item_id <= (int)Data::items.size() && data().party.size() > 0) {
+	if (data().party.size() == 0) {
+		return false;
+	}
+
+	switch (item->type) {
+		case RPG::Item::Type_weapon:
+		case RPG::Item::Type_shield:
+		case RPG::Item::Type_armor:
+		case RPG::Item::Type_helmet:
+		case RPG::Item::Type_accessory:
+			return item->use_skill && IsSkillUsable(item->skill_id, nullptr, true);
+		case RPG::Item::Type_special:
+			return IsSkillUsable(item->skill_id, nullptr, true);
+	}
+
+	if (Game_Temp::battle_running) {
 		switch (item->type) {
-			case RPG::Item::Type_weapon:
-			case RPG::Item::Type_shield:
-			case RPG::Item::Type_armor:
-			case RPG::Item::Type_helmet:
-			case RPG::Item::Type_accessory:
-				return item->use_skill && IsSkillUsable(item->skill_id, nullptr, true);
-			case RPG::Item::Type_special:
-				return IsSkillUsable(item->skill_id, nullptr, true);
+			case RPG::Item::Type_medicine:
+				return !item->occasion_field1;
+			case RPG::Item::Type_switch:
+				return item->occasion_battle;
 		}
-
-		if (Game_Temp::battle_running) {
-			switch (item->type) {
-				case RPG::Item::Type_medicine:
-					return !item->occasion_field1;
-				case RPG::Item::Type_switch:
-					return item->occasion_battle;
-			}
-		} else {
-			switch (item->type) {
-				case RPG::Item::Type_medicine:
-				case RPG::Item::Type_material:
-				case RPG::Item::Type_book:
-					return true;
-				case RPG::Item::Type_switch:
-					return item->occasion_field2;
-			}
+	} else {
+		switch (item->type) {
+			case RPG::Item::Type_medicine:
+			case RPG::Item::Type_material:
+			case RPG::Item::Type_book:
+				return true;
+			case RPG::Item::Type_switch:
+				return item->occasion_field2;
 		}
 	}
 
@@ -255,16 +257,49 @@ bool Game_Party::IsItemUsable(int item_id, const Game_Actor* target) const {
 bool Game_Party::UseItem(int item_id, Game_Actor* target) {
 	bool was_used = false;
 
+	auto* item = ReaderUtil::GetElement(Data::items, item_id);
+	if (!item) {
+		Output::Warning("UseItem: Can't use item with invalid ID %d", item_id);
+		return false;
+	}
+
+	bool do_skill = (item->type == RPG::Item::Type_special)
+		|| (item->use_skill && (
+				item->type == RPG::Item::Type_weapon
+				|| item->type == RPG::Item::Type_shield
+				|| item->type == RPG::Item::Type_armor
+				|| item->type == RPG::Item::Type_helmet
+				|| item->type == RPG::Item::Type_accessory
+				)
+				);
+
+	const RPG::Skill* skill = nullptr;
+	if (do_skill) {
+		skill = ReaderUtil::GetElement(Data::skills, item->skill_id);
+		if (skill == nullptr) {
+			Output::Warning("UseItem: Can't use item %d skill with invalid ID %d", item->ID, item->skill_id);
+			return false;
+		}
+	}
+
+	const Game_Actor* fixed_source = nullptr;
+	if (skill && skill->scope != RPG::Skill::Scope_self) {
+		fixed_source = GetHighestLeveledActorWhoCanUse(item);
+		if (fixed_source == nullptr) {
+			return false;
+		}
+	}
+
 	if (target) {
-		if (IsItemUsable(item_id, target)) {
-			was_used = target->UseItem(item_id);
+		const auto* source = fixed_source ? fixed_source : target;
+		if (IsItemUsable(item_id, source)) {
+			was_used = target->UseItem(item_id, source);
 		}
 	} else {
-		std::vector<Game_Actor*> actors = GetActors();
-		std::vector<Game_Actor*>::iterator it;
-		for (it = actors.begin(); it != actors.end(); ++it) {
-			if (IsItemUsable(item_id, (*it))) {
-				was_used |= (*it)->UseItem(item_id);
+		for (auto* actor: GetActors()) {
+			const auto* source = fixed_source ? fixed_source : actor;
+			if (IsItemUsable(item_id, source)) {
+				was_used |= actor->UseItem(item_id, source);
 			}
 		}
 	}
@@ -632,11 +667,13 @@ bool Game_Party::IsAnyControllable() {
 	return false;
 }
 
-Game_Actor* Game_Party::GetHighestLeveledActorWhoCanAct() const {
+Game_Actor* Game_Party::GetHighestLeveledActorWhoCanUse(const RPG::Item* item) const {
 	Game_Actor* best = nullptr;
 
 	for (auto* actor : GetActors()) {
-		if (actor->CanAct() && (best == nullptr || best->GetLevel() < actor->GetLevel())) {
+		if (actor->CanAct()
+				&& actor->IsItemUsable(item->ID)
+				&& (best == nullptr || best->GetLevel() < actor->GetLevel())) {
 			best = actor;
 		}
 	}
diff --git a/src/game_party.h b/src/game_party.h
index 6f7a8c07bf..82ae5daa79 100644
--- a/src/game_party.h
+++ b/src/game_party.h
@@ -342,11 +342,13 @@ class Game_Party : public Game_Party_Base {
 	bool IsAnyControllable();
 
 	/**
-	 * Gets the actor with the highest level who can act. If there are many, choose the one with the earliest position in the group.
+	 * Gets the actor with the highest level who can act and use the given item. If there are many, choose the one with the earliest position in the group.
+	 *
+	 * @param the item to check
 	 *
 	 * @return The first Highest leveled actor who can act.
 	 */
-	Game_Actor* GetHighestLeveledActorWhoCanAct() const;
+	Game_Actor* GetHighestLeveledActorWhoCanUse(const RPG::Item*) const;
 
 private:
 	const RPG::SaveInventory& data() const;