diff --git a/InnerDetector/InDetValidation/InDetPhysValMonitoring/src/InDetPhysValTruthDecoratorAlg.cxx b/InnerDetector/InDetValidation/InDetPhysValMonitoring/src/InDetPhysValTruthDecoratorAlg.cxx
index f977cd046f7a464b3fb51e5d490cfb2bf6480d3b..b6f1a3e804214b6704607123ed3d0ba739e50834 100644
--- a/InnerDetector/InDetValidation/InDetPhysValMonitoring/src/InDetPhysValTruthDecoratorAlg.cxx
+++ b/InnerDetector/InDetValidation/InDetPhysValMonitoring/src/InDetPhysValTruthDecoratorAlg.cxx
@@ -129,7 +129,7 @@ InDetPhysValTruthDecoratorAlg::decorateTruth(const xAOD::TruthParticle& particle
   const xAOD::TruthVertex* ptruthVertex(0);
   try{
     ptruthVertex = particle.prodVtx();
-  } catch (std::exception e) {
+  } catch (const std::exception& e) {
     if (not errorEmitted) {
       ATH_MSG_WARNING("A non existent production vertex was requested in calculating the track parameters d0 etc");
     }