diff --git a/src/diffCheck.hh b/src/diffCheck.hh
index 49ceec74..2e018738 100644
--- a/src/diffCheck.hh
+++ b/src/diffCheck.hh
@@ -5,7 +5,7 @@
 
 // diffCheck includes
 #include "diffCheck/log.hh"
-diffCheck::Log LOG = diffCheck::Log();
+const diffCheck::Log LOG = diffCheck::Log();
 
 #include "diffCheck/geometry/DFPointCloud.hh"
 #include "diffCheck/geometry/DFMesh.hh"