diff --git a/bigchaindb/pipelines/block.py b/bigchaindb/pipelines/block.py
index 5f372384..1f2e9017 100644
--- a/bigchaindb/pipelines/block.py
+++ b/bigchaindb/pipelines/block.py
@@ -67,28 +67,19 @@ class BlockPipeline:
                 AmountError):
             return None
 
-        if self.bigchain.transaction_exists(tx.id):
-            # if the transaction already exists, we must check whether
-            # it's in a valid or undecided block
-            tx, status = self.bigchain.get_transaction(tx.id,
-                                                       include_status=True)
-            if status == self.bigchain.TX_VALID \
-               or status == self.bigchain.TX_UNDECIDED:
-                # if the tx is already in a valid or undecided block,
-                # then it no longer should be in the backlog, or added
-                # to a new block. We can delete and drop it.
-                self.bigchain.delete_transaction(tx.id)
-                return None
-
-        tx_validated = self.bigchain.is_valid_transaction(tx)
-        if tx_validated:
-            return tx
-        else:
-            # if the transaction is not valid, remove it from the
-            # backlog
+        # If transaction is in any VALID or UNDECIDED block we
+        # should not include it again
+        if not self.bigchain.is_new_transaction(tx.id):
             self.bigchain.delete_transaction(tx.id)
             return None
 
+        # If transaction is not valid it should not be included
+        if not self.bigchain.is_valid_transaction(tx):
+            self.bigchain.delete_transaction(tx.id)
+            return None
+
+        return tx
+
     def create(self, tx, timeout=False):
         """Create a block.
 
diff --git a/bigchaindb/pipelines/vote.py b/bigchaindb/pipelines/vote.py
index 5f385f53..958e5b9c 100644
--- a/bigchaindb/pipelines/vote.py
+++ b/bigchaindb/pipelines/vote.py
@@ -90,7 +90,8 @@ class Vote:
             yield tx, block_id, num_tx
 
     def validate_tx(self, tx, block_id, num_tx):
-        """Validate a transaction.
+        """Validate a transaction. Transaction must also not be in any VALID
+           block.
 
         Args:
             tx (dict): the transaction to validate
@@ -101,7 +102,12 @@ class Vote:
             Three values are returned, the validity of the transaction,
             ``block_id``, ``num_tx``.
         """
-        return bool(self.bigchain.is_valid_transaction(tx)), block_id, num_tx
+        new = self.bigchain.is_new_transaction(tx.id, exclude_block_id=block_id)
+        if not new:
+            return False, block_id, num_tx
+
+        valid = bool(self.bigchain.is_valid_transaction(tx))
+        return valid, block_id, num_tx
 
     def vote(self, tx_validity, block_id, num_tx):
         """Collect the validity of transactions and cast a vote when ready.
diff --git a/tests/pipelines/test_vote.py b/tests/pipelines/test_vote.py
index e0b27f50..20beac1e 100644
--- a/tests/pipelines/test_vote.py
+++ b/tests/pipelines/test_vote.py
@@ -629,3 +629,17 @@ def test_start(mock_start, b):
     from bigchaindb.pipelines import vote
     vote.start()
     mock_start.assert_called_with()
+
+
+@pytest.mark.genesis
+def test_vote_no_double_inclusion(b):
+    from bigchaindb.pipelines import vote
+
+    tx = dummy_tx(b)
+    block = b.create_block([tx])
+    r = vote.Vote().validate_tx(tx, block.id, 1)
+    assert r == (True, block.id, 1)
+
+    b.write_block(block)
+    r = vote.Vote().validate_tx(tx, 'other_block_id', 1)
+    assert r == (False, 'other_block_id', 1)