diff --git a/src/openrct2/peep/staff.c b/src/openrct2/peep/staff.c
index 6725f712e4..d197541e21 100644
--- a/src/openrct2/peep/staff.c
+++ b/src/openrct2/peep/staff.c
@@ -406,7 +406,7 @@ void game_command_set_staff_order(sint32 *eax, sint32 *ebx, sint32 *ecx, sint32
 		if(order_id & 0x80){ // change costume
 			uint8 sprite_type = order_id & ~0x80;
 			sprite_type += 4;
-			if (sprite_type > countof(peep_slow_walking_types)) {
+			if (sprite_type >= countof(peep_slow_walking_types)) {
 				log_error("Invalid change costume order for sprite_type %u", sprite_type);
 				*ebx = MONEY32_UNDEFINED;
 				return;