diff --git a/agora/Agora/Effect/TreasuryWithdrawal.hs b/agora/Agora/Effect/TreasuryWithdrawal.hs
index 6bb2851..5bf451c 100644
--- a/agora/Agora/Effect/TreasuryWithdrawal.hs
+++ b/agora/Agora/Effect/TreasuryWithdrawal.hs
@@ -18,7 +18,7 @@ import GHC.Generics qualified as GHC
 import Generics.SOP (Generic, I (I))
 
 import Agora.Effect (makeEffect)
-import Agora.Utils (findTxOutByTxOutRef, paddValue, tcassert, tclet, tcmatch)
+import Agora.Utils (findTxOutByTxOutRef, isPubKey, paddValue, tcassert, tclet, tcmatch)
 import Plutarch.Api.V1 (
   PCredential (..),
   PTuple,
@@ -140,12 +140,6 @@ treasuryWithdrawalValidator currSymbol = makeEffect currSymbol $
         treasuryInputValuesSum = sumValues #$ ofTreasury # inputValues
         treasuryOutputValuesSum = sumValues #$ ofTreasury # outputValues
         receiverValuesSum = sumValues # datum.receivers
-        isPubkey = plam $ \cred ->
-          pmatch cred $
-            \case
-              PPubKeyCredential _ -> pcon PTrue
-              PScriptCredential _ -> pcon PFalse
-
         -- Constraints
         outputContentMatchesRecivers =
           pall # plam (\out -> pelem # out # outputValues)
@@ -165,7 +159,7 @@ treasuryWithdrawalValidator currSymbol = makeEffect currSymbol $
               ( \((pfield @"_0" #) . pfromData -> cred) ->
                   cred #== pfield @"credential" # effInput.address
                     #|| pelem # cred # datum.treasuries
-                    #|| isPubkey # pfromData cred
+                    #|| isPubKey # pfromData cred
               )
             # inputValues
 
diff --git a/agora/Agora/Utils.hs b/agora/Agora/Utils.hs
index 63cf022..1a6424b 100644
--- a/agora/Agora/Utils.hs
+++ b/agora/Agora/Utils.hs
@@ -60,6 +60,7 @@ module Agora.Utils (
   pmergeBy,
   phalve,
   isScriptAddress,
+  isPubKey,
 ) where
 
 --------------------------------------------------------------------------------
@@ -623,10 +624,15 @@ scriptHashFromAddress = phoistAcyclic $
 -- | Return true if the given address is a script address.
 isScriptAddress :: Term s (PAddress :--> PBool)
 isScriptAddress = phoistAcyclic $
-  plam $ \addr ->
-    pmatch (pfromData $ pfield @"credential" # addr) $ \case
-      PScriptCredential _ -> pconstant True
-      _ -> pconstant False
+  plam $ \addr -> pnot #$ isPubKey #$ pfromData $ pfield @"credential" # addr
+
+-- | Return true if the given credential is a pub-key-hash.
+isPubKey :: Term s (PCredential :--> PBool)
+isPubKey = phoistAcyclic $
+  plam $ \cred ->
+    pmatch cred $ \case
+      PScriptCredential _ -> pconstant False
+      _ -> pconstant True
 
 -- | Find all TxOuts sent to an Address
 findOutputsToAddress :: Term s (PBuiltinList (PAsData PTxOut) :--> PAddress :--> PBuiltinList (PAsData PTxOut))