diff --git a/internal/testutils/testutils.go b/internal/testutils/testutils.go
index 607d826f..3915ed82 100644
--- a/internal/testutils/testutils.go
+++ b/internal/testutils/testutils.go
@@ -30,15 +30,6 @@ func packRawPayload(version protocol.VersionNumber, frames []wire.Frame) []byte
 	return buf.Bytes()
 }
 
-// ComposeConnCloseFrame returns a new Connection Close frame with a generic error
-func ComposeConnCloseFrame() *wire.ConnectionCloseFrame {
-	return &wire.ConnectionCloseFrame{
-		IsApplicationError: true,
-		ErrorCode:          0,
-		ReasonPhrase:       "mitm attacker",
-	}
-}
-
 // ComposeInitialPacket returns an Initial packet encrypted under key
 // (the original destination connection ID) containing specified frames
 func ComposeInitialPacket(srcConnID protocol.ConnectionID, destConnID protocol.ConnectionID, version protocol.VersionNumber, key protocol.ConnectionID, frames []wire.Frame) []byte {
diff --git a/session_test.go b/session_test.go
index d2d41c8c..67fb5bf6 100644
--- a/session_test.go
+++ b/session_test.go
@@ -2965,7 +2965,10 @@ var _ = Describe("Client Session", func() {
 		// Illustrates that an injected Initial with a CONNECTION_CLOSE frame causes
 		// the connection to immediately break down
 		It("fails on Initial-level CONNECTION_CLOSE frame", func() {
-			connCloseFrame := testutils.ComposeConnCloseFrame()
+			connCloseFrame := &wire.ConnectionCloseFrame{
+				IsApplicationError: true,
+				ReasonPhrase:       "mitm attacker",
+			}
 			initialPacket := testutils.ComposeInitialPacket(destConnID, srcConnID, sess.version, destConnID, []wire.Frame{connCloseFrame})
 			tracer.EXPECT().ReceivedPacket(gomock.Any(), gomock.Any(), gomock.Any())
 			Expect(sess.handlePacketImpl(wrapPacket(initialPacket))).To(BeTrue())