diff --git a/javatests/com/google/gerrit/plugins/codeowners/backend/CodeOwnersExceptionHookTest.java b/javatests/com/google/gerrit/plugins/codeowners/backend/CodeOwnersExceptionHookTest.java
new file mode 100644
index 0000000..3c04fd0
--- /dev/null
+++ b/javatests/com/google/gerrit/plugins/codeowners/backend/CodeOwnersExceptionHookTest.java
@@ -0,0 +1,116 @@
+// Copyright (C) 2021 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.google.gerrit.plugins.codeowners.backend;
+
+import static com.google.common.truth.Truth.assertThat;
+import static com.google.gerrit.truth.OptionalSubject.assertThat;
+
+import com.google.common.collect.ImmutableList;
+import com.google.gerrit.plugins.codeowners.acceptance.AbstractCodeOwnersTest;
+import com.google.gerrit.plugins.codeowners.backend.config.InvalidPluginConfigurationException;
+import com.google.gerrit.server.ExceptionHook.Status;
+import java.util.Optional;
+import org.eclipse.jgit.errors.ConfigInvalidException;
+import org.junit.Before;
+import org.junit.Test;
+
+/** Tests for {@link CodeOwnersExceptionHook}. */
+public class CodeOwnersExceptionHookTest extends AbstractCodeOwnersTest {
+  private CodeOwnersExceptionHook codeOwnersExceptionHook;
+
+  @Before
+  public void setUpCodeOwnersPlugin() throws Exception {
+    codeOwnersExceptionHook = plugin.getSysInjector().getInstance(CodeOwnersExceptionHook.class);
+  }
+
+  @Test
+  public void skipRetryWithTrace() throws Exception {
+    assertThat(skipRetryWithTrace(newInvalidPluginConfigurationException())).isTrue();
+    assertThat(skipRetryWithTrace(newExceptionWithCause(newInvalidPluginConfigurationException())))
+        .isTrue();
+
+    assertThat(skipRetryWithTrace(newConfigInvalidException())).isTrue();
+    assertThat(skipRetryWithTrace(newExceptionWithCause(newConfigInvalidException()))).isTrue();
+
+    assertThat(skipRetryWithTrace(new Exception())).isFalse();
+    assertThat(skipRetryWithTrace(newExceptionWithCause(new Exception()))).isFalse();
+  }
+
+  @Test
+  public void getUserMessages() throws Exception {
+    InvalidPluginConfigurationException invalidPluginConfigurationException =
+        newInvalidPluginConfigurationException();
+    assertThat(getUserMessages(invalidPluginConfigurationException))
+        .containsExactly(invalidPluginConfigurationException.getMessage());
+
+    // TODO(ekempin): Make this assertion work
+    // assertThat(getUserMessages(newExceptionWithCause(invalidPluginConfigurationException)))
+    //    .containsExactly(invalidPluginConfigurationException.getMessage());
+
+    ConfigInvalidException configInvalidException = newConfigInvalidException();
+    assertThat(getUserMessages(configInvalidException))
+        .containsExactly(configInvalidException.getMessage());
+
+    // TODO(ekempin): Make this assertion work
+    // assertThat(getUserMessages(newExceptionWithCause(configInvalidException)))
+    //    .containsExactly(configInvalidException.getMessage());
+
+    assertThat(getUserMessages(new Exception())).isEmpty();
+    assertThat(getUserMessages(newExceptionWithCause(new Exception()))).isEmpty();
+  }
+
+  @Test
+  public void getStatus() throws Exception {
+    Status conflictStatus = Status.create(409, "Conflict");
+    assertThat(getStatus(newInvalidPluginConfigurationException()))
+        .value()
+        .isEqualTo(conflictStatus);
+    assertThat(getStatus(newExceptionWithCause(newInvalidPluginConfigurationException())))
+        .value()
+        .isEqualTo(conflictStatus);
+
+    assertThat(getStatus(newConfigInvalidException())).value().isEqualTo(conflictStatus);
+    assertThat(getStatus(newExceptionWithCause(newConfigInvalidException())))
+        .value()
+        .isEqualTo(conflictStatus);
+
+    assertThat(getStatus(new Exception())).isEmpty();
+    assertThat(getStatus(newExceptionWithCause(new Exception()))).isEmpty();
+  }
+
+  private boolean skipRetryWithTrace(Exception exception) {
+    return codeOwnersExceptionHook.skipRetryWithTrace("actionType", "actionName", exception);
+  }
+
+  private ImmutableList<String> getUserMessages(Exception exception) {
+    return codeOwnersExceptionHook.getUserMessages(exception, /* traceId= */ null);
+  }
+
+  private Optional<Status> getStatus(Exception exception) {
+    return codeOwnersExceptionHook.getStatus(exception);
+  }
+
+  private Exception newExceptionWithCause(Exception cause) {
+    return new Exception("exception1", new Exception("exception2", cause));
+  }
+
+  private InvalidPluginConfigurationException newInvalidPluginConfigurationException() {
+    return new InvalidPluginConfigurationException("code-owners", "message");
+  }
+
+  private ConfigInvalidException newConfigInvalidException() {
+    return new ConfigInvalidException("message");
+  }
+}