diff --git a/tests/unit/Android.bp b/tests/unit/Android.bp
index 327b6aad1c4..9d2d6865d07 100644
--- a/tests/unit/Android.bp
+++ b/tests/unit/Android.bp
@@ -32,6 +32,7 @@ android_test {
         "kotlinx_coroutines_test",
         "flag-junit",
         "Settings-testutils2",
+        "MediaDrmSettingsFlagsLib",
         // Don't add SettingsLib libraries here - you can use them directly as they are in the
         // instrumented Settings app.
     ],
diff --git a/tests/unit/src/com/android/settings/development/widevine/ForceL3FallbackPreferenceControllerTest.java b/tests/unit/src/com/android/settings/development/widevine/ForceL3FallbackPreferenceControllerTest.java
new file mode 100644
index 00000000000..f67a4af84fb
--- /dev/null
+++ b/tests/unit/src/com/android/settings/development/widevine/ForceL3FallbackPreferenceControllerTest.java
@@ -0,0 +1,136 @@
+/*
+* Copyright (C) 2023 The Android Open Source Project
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+*      http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+package com.android.settings.development.widevine;
+
+import static com.google.common.truth.Truth.assertThat;
+import static org.junit.Assume.assumeTrue;
+import static org.junit.Assume.assumeNoException;
+
+import android.content.Context;
+import android.media.MediaDrm;
+import android.media.UnsupportedSchemeException;
+import android.media.NotProvisionedException;
+import android.sysprop.WidevineProperties;
+import android.util.Log;
+import android.content.Context;
+
+import com.android.settings.media_drm.Flags;
+import android.platform.test.flag.junit.SetFlagsRule;
+
+import androidx.preference.SwitchPreference;
+import androidx.test.core.app.ApplicationProvider;
+import androidx.test.ext.junit.runners.AndroidJUnit4;
+
+import org.junit.Before;
+import org.junit.Rule;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+
+import java.util.UUID;
+
+@RunWith(AndroidJUnit4.class)
+public class ForceL3FallbackPreferenceControllerTest {
+
+    private static final String PREF_KEY = "force_l3_fallback";
+    private static final UUID WIDEVINE_UUID =
+        new UUID(0xEDEF8BA979D64ACEL, 0xA3C827DCD51D21EDL);
+    private static final String TAG = "ForceL3FallbackPreferenceControllerTest";
+
+    @Rule public final SetFlagsRule mSetFlagsRule = new SetFlagsRule();
+
+    private Context mContext;
+    private ForceL3FallbackPreferenceController mController;
+    private SwitchPreference mPreference;
+
+    @Before
+    public void setUp() {
+        mContext = ApplicationProvider.getApplicationContext();
+        mController = new ForceL3FallbackPreferenceController(mContext, PREF_KEY);
+        mPreference = new SwitchPreference(mContext);
+        WidevineProperties.forcel3_enabled(false);
+    }
+
+    @Test
+    public void updateState_flagEnabled_checkPreference() {
+        mSetFlagsRule.enableFlags(Flags.FLAG_FORCE_L3_ENABLED);
+        mController.updateState(mPreference);
+        assertThat(mPreference.isEnabled()).isTrue();
+        assertThat(mPreference.isChecked()).isFalse();
+        assertThat(WidevineProperties.forcel3_enabled().orElse(false)).isFalse();
+
+        // Toggle to true
+        mController.setChecked(true);
+        mController.updateState(mPreference);
+        assertThat(WidevineProperties.forcel3_enabled().orElse(false)).isTrue();
+        assertThat(mPreference.isEnabled()).isTrue();
+        assertThat(mPreference.isChecked()).isTrue();
+
+        // Toggle to false
+        mController.setChecked(false);
+        mController.updateState(mPreference);
+        assertThat(WidevineProperties.forcel3_enabled().orElse(false)).isFalse();
+        assertThat(mPreference.isEnabled()).isTrue();
+        assertThat(mPreference.isChecked()).isFalse();
+
+        // Test flag rollback
+        mController.setChecked(true);
+        mController.updateState(mPreference);
+        assertThat(mPreference.isChecked()).isTrue();
+        assertThat(WidevineProperties.forcel3_enabled().orElse(false)).isTrue();
+        mSetFlagsRule.disableFlags(Flags.FLAG_FORCE_L3_ENABLED);
+        mController.updateState(mPreference);
+        assertThat(mPreference.isEnabled()).isFalse();
+        assertThat(mPreference.isChecked()).isFalse();
+        assertThat(WidevineProperties.forcel3_enabled().orElse(false)).isFalse();
+    }
+
+    @Test
+    public void updateState_flagDisabled_checkPreference() {
+        mSetFlagsRule.disableFlags(Flags.FLAG_FORCE_L3_ENABLED);
+        mController.updateState(mPreference);
+        assertThat(mPreference.isEnabled()).isFalse();
+    }
+
+    @Test
+    public void updateState_checkWidevine() throws Exception {
+        MediaDrm drm;
+        try {
+            drm = new MediaDrm(WIDEVINE_UUID);
+            assumeTrue(drm.getPropertyString("securityLevel").equals("L1"));
+            mSetFlagsRule.enableFlags(Flags.FLAG_FORCE_L3_ENABLED);
+            drm.close();
+        } catch (UnsupportedSchemeException ex) {
+            assumeNoException(ex);
+        }
+
+        // L3 enforced
+        mController.setChecked(true);
+        mController.updateState(mPreference);
+        assertThat(WidevineProperties.forcel3_enabled().orElse(false)).isTrue();
+        assertThat(mPreference.isEnabled()).isTrue();
+        assertThat(mPreference.isChecked()).isTrue();
+        drm = new MediaDrm(WIDEVINE_UUID);
+        assertThat(drm.getPropertyString("securityLevel")).isEqualTo("L3");
+
+        // Switch back to L1
+        mController.setChecked(false);
+        mController.updateState(mPreference);
+        drm.close();
+        drm = new MediaDrm(WIDEVINE_UUID);
+        assertThat(drm.getPropertyString("securityLevel")).isEqualTo("L1");
+    }
+}