diff --git a/src/ripple/app/transactors/SetAccount.cpp b/src/ripple/app/transactors/SetAccount.cpp
index 423a9e7e7f..58c3f5c2fc 100644
--- a/src/ripple/app/transactors/SetAccount.cpp
+++ b/src/ripple/app/transactors/SetAccount.cpp
@@ -265,18 +265,19 @@ public:
 
         if (mTxn.isFieldPresent (sfMessageKey))
         {
-            Blob messageKey = mTxn.getFieldVL (sfMessageKey);
+            Blob const messageKey = mTxn.getFieldVL (sfMessageKey);
+
+            if (messageKey.size () > PUBLIC_BYTES_MAX)
+            {
+                m_journal.trace << "message key too long";
+                return telBAD_PUBLIC_KEY;
+            }
 
             if (messageKey.empty ())
             {
                 m_journal.debug << "set message key";
                 mTxnAccount->makeFieldAbsent (sfMessageKey);
             }
-            if (messageKey.size () > PUBLIC_BYTES_MAX)
-            {
-                m_journal.trace << "message key too long";
-                return telBAD_PUBLIC_KEY;
-            }
             else
             {
                 m_journal.debug << "set message key";