diff --git a/biometrics/fingerprint/aidl/default/WorkerThread.cpp b/biometrics/fingerprint/aidl/default/WorkerThread.cpp
index d1a63d0..34ebb5c 100644
--- a/biometrics/fingerprint/aidl/default/WorkerThread.cpp
+++ b/biometrics/fingerprint/aidl/default/WorkerThread.cpp
@@ -31,7 +31,10 @@
 WorkerThread::~WorkerThread() {
     // This is a signal for threadFunc to terminate as soon as possible, and a hint for schedule
     // that it doesn't need to do any work.
-    mIsDestructing = true;
+    {
+        std::unique_lock<std::mutex> lock(mQueueMutex);
+        mIsDestructing = true;
+    }
     mQueueCond.notify_all();
     mThread.join();
 }