diff --git a/src/js/assayJS.js b/src/js/assayJS.js
index dbd606c788fbfd32f5d3f8584e0071efe12a79e0..06ea5fcaad4d35b445b62e62fcda34143fee52ba 100644
--- a/src/js/assayJS.js
+++ b/src/js/assayJS.js
@@ -79,7 +79,8 @@ globalThis.inferiorRaceP = function(slave) {
 globalThis.isLeaderP = function(slave) {
 	/** @type {FC.SlaveStateOrZero[]} */
 	const leaders = [V.HeadGirl, V.Bodyguard, V.Recruiter, V.Concubine, V.Nurse, S.Attendant, V.Matron, V.Madam, V.DJ, V.Milkmaid, V.Farmer, V.Stewardess, V.Schoolteacher, V.Wardeness];
-	return leaders.some(leader => leader.ID && leader.ID === slave.ID);
+
+	return leaders.some(leader => leader && leader.ID && leader.ID === slave.ID);
 };
 
 /**