diff --git a/src/main/java/com/google/devtools/build/lib/events/BUILD b/src/main/java/com/google/devtools/build/lib/events/BUILD
index 217315d8da8ea4..8ee748003258c9 100644
--- a/src/main/java/com/google/devtools/build/lib/events/BUILD
+++ b/src/main/java/com/google/devtools/build/lib/events/BUILD
@@ -18,6 +18,7 @@ java_library(
         exclude = ["EventBusEventHandler.java"],
     ),
     deps = [
+        "//src/main/java/com/google/devtools/build/lib/unsafe:string",
         "//src/main/java/com/google/devtools/build/lib/util:string_encoding",
         "//src/main/java/com/google/devtools/build/lib/util/io:out-err",
         "//src/main/java/net/starlark/java/eval",
diff --git a/src/main/java/com/google/devtools/build/lib/events/Event.java b/src/main/java/com/google/devtools/build/lib/events/Event.java
index ded7ba6a50ccc3..86b326f4369132 100644
--- a/src/main/java/com/google/devtools/build/lib/events/Event.java
+++ b/src/main/java/com/google/devtools/build/lib/events/Event.java
@@ -15,10 +15,10 @@
 
 import static com.google.common.base.Preconditions.checkNotNull;
 import static com.google.common.collect.ImmutableList.toImmutableList;
-import static java.nio.charset.StandardCharsets.UTF_8;
 import static java.util.Comparator.comparing;
 
 import com.google.common.collect.ImmutableClassToInstanceMap;
+import com.google.devtools.build.lib.unsafe.StringUnsafe;
 import com.google.errorprone.annotations.CheckReturnValue;
 import java.io.IOException;
 import java.util.Arrays;
@@ -84,16 +84,21 @@ public EventKind getKind() {
   }
 
   public String getMessage() {
-    return message instanceof String ? (String) message : new String((byte[]) message, UTF_8);
+    return message instanceof String
+        ? (String) message
+        : StringUnsafe.newInstance((byte[]) message, StringUnsafe.LATIN1);
   }
 
   /**
-   * Returns this event's message as a {@link byte[]}. If this event was instantiated using a {@link
-   * String}, the returned byte array is encoded using {@link
-   * java.nio.charset.StandardCharsets#UTF_8}.
+   * Returns this event's message as a {@link byte[]} by unwrapping Bazel's {@link
+   * com.google.devtools.build.lib.util.StringEncoding internal string encoding}.
+   *
+   * <p>Caller's must not modify the returned array.
    */
   public byte[] getMessageBytes() {
-    return message instanceof byte[] ? (byte[]) message : ((String) message).getBytes(UTF_8);
+    return message instanceof byte[]
+        ? (byte[]) message
+        : StringUnsafe.getInternalStringBytes((String) message);
   }
 
   /** Returns the property value associated with {@code type} if any, and {@code null} otherwise. */
diff --git a/src/main/java/com/google/devtools/build/lib/events/PrintingEventHandler.java b/src/main/java/com/google/devtools/build/lib/events/PrintingEventHandler.java
index 93a8908cb7f914..2288971b86ba6e 100644
--- a/src/main/java/com/google/devtools/build/lib/events/PrintingEventHandler.java
+++ b/src/main/java/com/google/devtools/build/lib/events/PrintingEventHandler.java
@@ -13,6 +13,7 @@
 // limitations under the License.
 package com.google.devtools.build.lib.events;
 
+import com.google.devtools.build.lib.unsafe.StringUnsafe;
 import com.google.devtools.build.lib.util.io.OutErr;
 import java.io.IOException;
 import java.nio.charset.StandardCharsets;
@@ -102,7 +103,7 @@ public void handle(Event event) {
             builder.append(event.getLocation()).append(": ");
           }
           builder.append(event.getMessage()).append("\n");
-          outErr.getErrorStream().write(builder.toString().getBytes(StandardCharsets.UTF_8));
+          outErr.getErrorStream().write(StringUnsafe.getInternalStringBytes(builder.toString()));
           outErr.getErrorStream().flush();
         }
       }
diff --git a/src/main/java/com/google/devtools/build/lib/util/io/AnsiTerminal.java b/src/main/java/com/google/devtools/build/lib/util/io/AnsiTerminal.java
index 743157d47c03dc..a70d0a081df5c4 100644
--- a/src/main/java/com/google/devtools/build/lib/util/io/AnsiTerminal.java
+++ b/src/main/java/com/google/devtools/build/lib/util/io/AnsiTerminal.java
@@ -15,6 +15,7 @@
 
 import static java.nio.charset.StandardCharsets.US_ASCII;
 
+import com.google.devtools.build.lib.unsafe.StringUnsafe;
 import java.io.IOException;
 import java.io.OutputStream;
 
@@ -139,9 +140,8 @@ public void textMagenta() throws IOException {
   }
 
   /** Set the terminal title. */
-  @SuppressWarnings("DefaultCharset")
   public void setTitle(String title) throws IOException {
-    writeBytes(osc, setTermTitle, title.getBytes(), st);
+    writeBytes(osc, setTermTitle, StringUnsafe.getInternalStringBytes(title), st);
   }
 
   /**
@@ -149,9 +149,8 @@ public void setTitle(String title) throws IOException {
    *
    * @param text the text to write
    */
-  @SuppressWarnings("DefaultCharset")
   public void writeString(String text) throws IOException {
-    out.write(text.getBytes());
+    out.write(StringUnsafe.getInternalStringBytes(text));
   }
 
   /**
diff --git a/src/main/java/com/google/devtools/build/lib/util/io/BUILD b/src/main/java/com/google/devtools/build/lib/util/io/BUILD
index 9e366a2426b20b..f21afd1a773f25 100644
--- a/src/main/java/com/google/devtools/build/lib/util/io/BUILD
+++ b/src/main/java/com/google/devtools/build/lib/util/io/BUILD
@@ -73,6 +73,7 @@ java_library(
     srcs = OUT_ERR_SRCS,
     deps = [
         "//src/main/java/com/google/devtools/build/lib/concurrent:thread_safety",
+        "//src/main/java/com/google/devtools/build/lib/unsafe:string",
         "//third_party:flogger",
         "//third_party:guava",
     ],
diff --git a/src/test/java/com/google/devtools/build/lib/events/BUILD b/src/test/java/com/google/devtools/build/lib/events/BUILD
index 801edf02ffd21d..ed10c4cb494d8c 100644
--- a/src/test/java/com/google/devtools/build/lib/events/BUILD
+++ b/src/test/java/com/google/devtools/build/lib/events/BUILD
@@ -19,6 +19,8 @@ java_library(
     deps = [
         "//src/main/java/com/google/devtools/build/lib/events",
         "//src/main/java/com/google/devtools/build/lib/events:event_bus_event_handler",
+        "//src/main/java/com/google/devtools/build/lib/unsafe:string",
+        "//src/main/java/com/google/devtools/build/lib/util:string_encoding",
         "//src/main/java/com/google/devtools/build/lib/util/io:out-err",
         "//src/main/java/net/starlark/java/eval",
         "//src/main/java/net/starlark/java/syntax",
diff --git a/src/test/java/com/google/devtools/build/lib/events/EventTest.java b/src/test/java/com/google/devtools/build/lib/events/EventTest.java
index c402ce97047aac..c481ce8d25a40d 100644
--- a/src/test/java/com/google/devtools/build/lib/events/EventTest.java
+++ b/src/test/java/com/google/devtools/build/lib/events/EventTest.java
@@ -14,7 +14,8 @@
 package com.google.devtools.build.lib.events;
 
 import static com.google.common.truth.Truth.assertThat;
-import static java.nio.charset.StandardCharsets.UTF_8;
+import static java.nio.charset.StandardCharsets.ISO_8859_1;
+import static java.nio.charset.StandardCharsets.US_ASCII;
 import static org.mockito.Mockito.inOrder;
 import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.verify;
@@ -22,6 +23,8 @@
 import com.google.common.collect.ImmutableList;
 import com.google.common.testing.EqualsTester;
 import com.google.devtools.build.lib.events.Event.ProcessOutput;
+import com.google.devtools.build.lib.unsafe.StringUnsafe;
+import com.google.devtools.build.lib.util.StringEncoding;
 import net.starlark.java.eval.Mutability;
 import net.starlark.java.eval.StarlarkSemantics;
 import net.starlark.java.eval.StarlarkThread;
@@ -47,22 +50,17 @@ public void eventKindMessage() {
 
   @Test
   public void eventMessageEncoding() {
-    String message = "Bazel \u1f33f";
+    String message = StringEncoding.unicodeToInternal("Bazel ἳf");
 
     Event stringEvent = Event.of(EventKind.WARNING, message);
-    Event stringEvent2 = Event.of(EventKind.WARNING, "Bazel \u1f33f");
     assertThat(stringEvent.getMessage()).isEqualTo(message);
-    assertThat(stringEvent.getMessageBytes()).isEqualTo(message.getBytes(UTF_8));
+    assertThat(stringEvent.getMessageBytes()).isEqualTo(message.getBytes(ISO_8859_1));
 
-    Event byteArrayEvent = Event.of(EventKind.WARNING, message.getBytes(UTF_8));
-    Event byteArrayEvent2 = Event.of(EventKind.WARNING, "Bazel \u1f33f".getBytes(UTF_8));
+    Event byteArrayEvent = Event.of(EventKind.WARNING, StringUnsafe.getByteArray(message));
     assertThat(byteArrayEvent.getMessage()).isEqualTo(message);
-    assertThat(byteArrayEvent.getMessageBytes()).isEqualTo(message.getBytes(UTF_8));
+    assertThat(byteArrayEvent.getMessageBytes()).isEqualTo(message.getBytes(ISO_8859_1));
 
-    new EqualsTester()
-        .addEqualityGroup(stringEvent, stringEvent2)
-        .addEqualityGroup(byteArrayEvent, byteArrayEvent2)
-        .testEquals();
+    assertThat(stringEvent).isNotEqualTo(byteArrayEvent);
   }
 
   @Test
@@ -77,7 +75,7 @@ public void eventLocationSensitiveToString() {
 
   @Test
   public void messageReference() throws Exception {
-    byte[] messageBytes = "message".getBytes(UTF_8);
+    byte[] messageBytes = "message".getBytes(US_ASCII);
     Event event = Event.of(EventKind.WARNING, messageBytes);
     assertThat(event.getMessageBytes()).isEqualTo(messageBytes);
   }
@@ -182,9 +180,9 @@ public void tagIsSameAsStringProperty() {
   @Test
   public void testWithProcessOutput() throws Exception {
     String stdoutPath = "/stdout";
-    byte[] stdout = "some stdout output".getBytes(UTF_8);
+    byte[] stdout = "some stdout output".getBytes(US_ASCII);
     String stderrPath = "/stderr";
-    byte[] stderr = "some stderr error".getBytes(UTF_8);
+    byte[] stderr = "some stderr error".getBytes(US_ASCII);
 
     ProcessOutput testProcessOutput =
         new ProcessOutput() {