diff --git a/src/plugin-host/plugin-events/event-arguments/pre-user-score-changed-event-arguments.ts b/src/plugin-host/plugin-events/event-arguments/pre-user-score-changed-event-arguments.ts
index d2c50b1..00df710 100644
--- a/src/plugin-host/plugin-events/event-arguments/pre-user-score-changed-event-arguments.ts
+++ b/src/plugin-host/plugin-events/event-arguments/pre-user-score-changed-event-arguments.ts
@@ -26,11 +26,21 @@ export class PreUserScoreChangedEventArguments extends PluginEventArguments {
     public set changeInScore(newChangeInScore: number) {
         if (isNaN(newChangeInScore)) {
             console.error(`Failed to set new score change for source '${this.nameOfOriginPlugin}' for reason '${this.reason}': not a number`);
-        } else if (!this.immutable) {
+        } else if (this.isImmutable) {
+            console.warn(`Cannot change the value for an immutable event from source '${this.nameOfOriginPlugin}' with reason '${this.reason}'.`);
+        } else {
             this.myChangeInScore = newChangeInScore;
         }
     }
 
+    /**
+     * Indicates if the event is immutable.
+     */
+    public get immutable(): boolean {
+        return this.isImmutable;
+    }
+
+    private isImmutable = false;
     private myChangeInScore = 0;
 
     /**
@@ -43,10 +53,11 @@ export class PreUserScoreChangedEventArguments extends PluginEventArguments {
    * not being caused by a plugin.
    * @param immutable Disallows the score delta to be changed.
    */
-    constructor(chat: Chat, user: User, changeInScore: number, reason: string, nameOfOriginPlugin: string, private immutable: boolean) {
+    constructor(chat: Chat, user: User, changeInScore: number, reason: string, nameOfOriginPlugin: string, immutable: boolean) {
         super(nameOfOriginPlugin, reason);
         this.chat = chat;
         this.user = user;
-        this.changeInScore = changeInScore;
+        this.myChangeInScore = changeInScore;
+        this.isImmutable = immutable;
     }
 }