diff --git a/quic/core/quic_dispatcher.cc b/quic/core/quic_dispatcher.cc
index 37f1901..aeda8fc 100644
--- a/quic/core/quic_dispatcher.cc
+++ b/quic/core/quic_dispatcher.cc
@@ -327,7 +327,13 @@
     QUIC_DLOG(INFO) << "Packet with short destination connection ID "
                     << server_connection_id << " expected "
                     << static_cast<int>(expected_server_connection_id_length_);
-    ProcessUnauthenticatedHeaderFate(kFateTimeWait, server_connection_id, form,
+    QuicPacketFate fate = kFateDrop;
+    if (!GetQuicReloadableFlag(quic_drop_invalid_small_initial_connection_id)) {
+      fate = kFateTimeWait;
+    } else {
+      QUIC_RELOADABLE_FLAG_COUNT(quic_drop_invalid_small_initial_connection_id);
+    }
+    ProcessUnauthenticatedHeaderFate(fate, server_connection_id, form,
                                      version_flag, version);
     return true;
   }
diff --git a/quic/core/quic_dispatcher_test.cc b/quic/core/quic_dispatcher_test.cc
index 43c34f0..3b0c92b 100644
--- a/quic/core/quic_dispatcher_test.cc
+++ b/quic/core/quic_dispatcher_test.cc
@@ -838,6 +838,25 @@
   ProcessPacket(client_address, TestConnectionId(1), true, SerializeCHLO());
 }
 
+TEST_F(QuicDispatcherTest, ProcessPacketWithInvalidShortInitialConnectionId) {
+  SetQuicReloadableFlag(quic_drop_invalid_small_initial_connection_id, true);
+  // Enable v47 otherwise we cannot create a packet with a short connection ID.
+  SetQuicReloadableFlag(quic_enable_version_47, true);
+  CreateTimeWaitListManager();
+
+  QuicSocketAddress client_address(QuicIpAddress::Loopback4(), 1);
+
+  // dispatcher_ should drop this packet.
+  EXPECT_CALL(*dispatcher_,
+              CreateQuicSession(_, client_address, QuicStringPiece("hq"), _))
+      .Times(0);
+  EXPECT_CALL(*time_wait_list_manager_, ProcessPacket(_, _, _, _, _)).Times(0);
+  EXPECT_CALL(*time_wait_list_manager_,
+              AddConnectionIdToTimeWait(_, _, _, _, _))
+      .Times(0);
+  ProcessPacket(client_address, EmptyQuicConnectionId(), true, SerializeCHLO());
+}
+
 TEST_F(QuicDispatcherTest, OKSeqNoPacketProcessed) {
   QuicSocketAddress client_address(QuicIpAddress::Loopback4(), 1);
   QuicConnectionId connection_id = TestConnectionId(1);
@@ -918,6 +937,7 @@
 // Packets with truncated connection IDs should be dropped.
 TEST_F(QuicDispatcherTestStrayPacketConnectionId,
        StrayPacketTruncatedConnectionId) {
+  SetQuicReloadableFlag(quic_drop_invalid_small_initial_connection_id, true);
   CreateTimeWaitListManager();
 
   QuicSocketAddress client_address(QuicIpAddress::Loopback4(), 1);
@@ -925,8 +945,6 @@
   EXPECT_CALL(*dispatcher_, CreateQuicSession(_, _, QuicStringPiece("hq"), _))
       .Times(0);
   if (VersionHasIetfInvariantHeader(
-          CurrentSupportedVersions()[0].transport_version) &&
-      !QuicUtils::VariableLengthConnectionIdAllowedForVersion(
           CurrentSupportedVersions()[0].transport_version)) {
     // This IETF packet has invalid connection ID length.
     EXPECT_CALL(*time_wait_list_manager_, ProcessPacket(_, _, _, _, _))
@@ -935,10 +953,8 @@
                 AddConnectionIdToTimeWait(_, _, _, _, _))
         .Times(0);
   } else {
-    // This is either:
-    // - a GQUIC packet considered as IETF QUIC packet with short header
-    // with unacceptable packet number or
-    // - an IETF QUIC packet with bad connection ID length which is rejected.
+    // This is a GQUIC packet considered as IETF QUIC packet with short header
+    // with unacceptable packet number.
     EXPECT_CALL(*time_wait_list_manager_, ProcessPacket(_, _, _, _, _))
         .Times(1);
     EXPECT_CALL(*time_wait_list_manager_,