diff --git a/tests/unit/test_parallel_harness.h b/tests/unit/test_parallel_harness.h
index 7b6dfe9b2f..d496b38c20 100644
--- a/tests/unit/test_parallel_harness.h
+++ b/tests/unit/test_parallel_harness.h
@@ -77,7 +77,7 @@ struct MPISingletonMultiTest {
   }
 
 public:
-  const MPI_Comm getComm() { return comm_; }
+  MPI_Comm getComm() { return comm_; }
 
 private:
   MPI_Comm comm_;