diff --git a/core/types/bal/bal.go b/core/types/bal/bal.go
index 86dc8e5426..dfa4e8c4bf 100644
--- a/core/types/bal/bal.go
+++ b/core/types/bal/bal.go
@@ -144,7 +144,9 @@ func (b *ConstructionBlockAccessList) PrettyPrint() string {
 
 // Copy returns a deep copy of the access list.
 func (b *ConstructionBlockAccessList) Copy() *ConstructionBlockAccessList {
-	res := NewConstructionBlockAccessList()
+	res := ConstructionBlockAccessList{
+		Accounts: make(map[common.Address]*ConstructionAccountAccess, len(b.Accounts)),
+	}
 	for addr, aa := range b.Accounts {
 		var aaCopy ConstructionAccountAccess