diff --git a/src/branch_tier.hpp b/src/branch_tier.hpp
index 4fe7d8b8..bbf680bd 100644
--- a/src/branch_tier.hpp
+++ b/src/branch_tier.hpp
@@ -10,7 +10,6 @@ class BranchTier
 {
 public:
   BranchTier();
-  BranchTier(BranchTier &);
   BranchTier(toml::value const &);
 
 public: