diff --git a/code/_onclick/item_attack.dm b/code/_onclick/item_attack.dm
index c0fc84bd745..2b2b5428f59 100644
--- a/code/_onclick/item_attack.dm
+++ b/code/_onclick/item_attack.dm
@@ -84,7 +84,7 @@ avoid code duplication. This includes items that may sometimes act as a standard
 
 /obj/item/proc/swing_attack(atom/A, mob/user, params)
 	var/holdinghand = user.get_inventory_slot(src)
-	if(params && params["mech"])
+	if(params && islist(params) && params["mech"])
 		holdinghand = params["mech_hand"]
 	var/turf/R
 	var/turf/C