diff --git a/blockchain/chain.go b/blockchain/chain.go
index 5287ca0c..8321b0c4 100644
--- a/blockchain/chain.go
+++ b/blockchain/chain.go
@@ -1068,9 +1068,16 @@ func (b *BlockChain) reorganizeChain(detachNodes, attachNodes *list.List) error
 				return err
 			}
 		} else {
-			// Check that the block txOuts are valid by checking the utreexo proof and
-			// extra data and then update the accumulator.
-			err := b.utreexoView.ProcessUData(block, b.bestChain, block.MsgBlock().UData)
+			err := b.utreexoView.VerifyUData(block, b.bestChain, block.MsgBlock().UData)
+			if err != nil {
+				return fmt.Errorf("reorganizeChain fail while attaching "+
+					"block %s. Error: %v", block.Hash().String(), err)
+			}
+			err = b.utreexoView.ProcessUData(block, b.bestChain, block.MsgBlock().UData)
+			if err != nil {
+				return fmt.Errorf("reorganizeChain fail while attaching "+
+					"block %s. Error: %v", block.Hash().String(), err)
+			}
 			if err != nil {
 				return fmt.Errorf("reorganizeChain fail while attaching "+
 					"block %s. Error: %v", block.Hash().String(), err)
@@ -1329,7 +1336,14 @@ func (b *BlockChain) verifyReorganizationValidity(detachNodes, attachNodes *list
 			} else {
 				// Check that the block txOuts are valid by checking the utreexo proof and
 				// extra data and then update the accumulator.
-				err := utreexoView.ProcessUData(block, b.bestChain, block.MsgBlock().UData)
+				err := utreexoView.VerifyUData(block, b.bestChain, block.MsgBlock().UData)
+				if err != nil {
+					return nil, nil, nil,
+						fmt.Errorf("verifyReorganizationValidity fail "+
+							"while attaching block %s. Error %v",
+							block.Hash().String(), err)
+				}
+				err = utreexoView.ProcessUData(block, b.bestChain, block.MsgBlock().UData)
 				if err != nil {
 					return nil, nil, nil,
 						fmt.Errorf("verifyReorganizationValidity fail "+
@@ -1369,6 +1383,15 @@ func (b *BlockChain) verifyReorganizationValidity(detachNodes, attachNodes *list
 			}
 			return nil, nil, nil, err
 		}
+		if utreexoView != nil {
+			err = utreexoView.ProcessUData(block, b.bestChain, block.MsgBlock().UData)
+			if err != nil {
+				return nil, nil, nil,
+					fmt.Errorf("verifyReorganizationValidity fail "+
+						"while attaching block %s. Error %v",
+						block.Hash().String(), err)
+			}
+		}
 		b.index.SetStatusFlags(n, statusValid)
 	}
 
@@ -1445,16 +1468,22 @@ func (b *BlockChain) connectBestChain(node *blockNode, block *btcutil.Block, fla
 		if b.utreexoView != nil {
 			if fastAdd {
 				// Check that the block txOuts are valid by checking the utreexo proof and
-				// extra data and then update the accumulator.
-				err := b.utreexoView.ProcessUData(block, b.bestChain, block.MsgBlock().UData)
+				// the leaf data.
+				err := b.utreexoView.VerifyUData(block, b.bestChain, block.MsgBlock().UData)
 				if err != nil {
 					return false, fmt.Errorf("connectBestChain fail on block %s. "+
 						"Error: %v", block.Hash().String(), err)
 				}
 			}
+			// Update the accumulator.
+			err := b.utreexoView.ProcessUData(block, b.bestChain, block.MsgBlock().UData)
+			if err != nil {
+				return false, fmt.Errorf("connectBestChain fail on block %s. "+
+					"Error: %v", block.Hash().String(), err)
+			}
 			view := NewUtxoViewpoint()
 			view.SetBestHash(parentHash)
-			err := view.BlockToUtxoView(block)
+			err = view.BlockToUtxoView(block)
 			if err != nil {
 				return false, err
 			}
diff --git a/blockchain/utreexoviewpoint.go b/blockchain/utreexoviewpoint.go
index 9c3596aa..1b4bdfb2 100644
--- a/blockchain/utreexoviewpoint.go
+++ b/blockchain/utreexoviewpoint.go
@@ -46,8 +46,7 @@ func (uview *UtreexoViewpoint) CopyWithRoots() *UtreexoViewpoint {
 	return newUview
 }
 
-// ProcessUData checks that the accumulator proof and the utxo data included in the UData
-// passes consensus and then it updates the underlying accumulator.
+// ProcessUData updates the underlying accumulator. It does NOT check if the verification passes.
 func (uview *UtreexoViewpoint) ProcessUData(block *btcutil.Block,
 	bestChain *chainView, ud *wire.UData) error {
 
@@ -57,6 +56,32 @@ func (uview *UtreexoViewpoint) ProcessUData(block *btcutil.Block,
 	if err != nil {
 		return err
 	}
+
+	dels, err := ExtractAccumulatorDels(block, bestChain, ud.RememberIdx)
+	if err != nil {
+		return err
+	}
+
+	// Update the underlying accumulator.
+	updateData, err := uview.Modify(ud, adds, dels)
+	if err != nil {
+		return fmt.Errorf("ProcessUData fail. Error: %v", err)
+	}
+
+	// Add the utreexo data to the block.
+	block.SetUtreexoUpdateData(updateData)
+	block.SetUtreexoAdds(adds)
+
+	return nil
+}
+
+// VerifyUData checks the accumulator proof to ensure that the leaf preimages exist in the
+// accumulator.
+func (uview *UtreexoViewpoint) VerifyUData(block *btcutil.Block,
+	bestChain *chainView, ud *wire.UData) error {
+
+	// Extracts the block into additions and deletions that will be processed.
+	// Adds correspond to newly created UTXOs and dels correspond to STXOs.
 	dels, err := ExtractAccumulatorDels(block, bestChain, ud.RememberIdx)
 	if err != nil {
 		return err
@@ -84,17 +109,13 @@ func (uview *UtreexoViewpoint) ProcessUData(block *btcutil.Block,
 		}
 	}
 
-	// Update the underlying accumulator.
-	updateData, err := uview.Modify(ud, adds, dels)
-	if err != nil {
-		return fmt.Errorf("ProcessUData fail. Error: %v", err)
+	// TODO we should be verifying here but aren't as the accumulator.Verify
+	// function expects a complete proof.
+	if uview.proofInterval != 1 {
+		return nil
 	}
 
-	// Add the utreexo data to the block.
-	block.SetUtreexoUpdateData(updateData)
-	block.SetUtreexoAdds(adds)
-
-	return nil
+	return uview.accumulator.Verify(dels, ud.AccProof, false)
 }
 
 // AddProof first checks that the utreexo proofs are valid. If it is valid,
@@ -124,7 +145,7 @@ func (uview *UtreexoViewpoint) Modify(ud *wire.UData,
 	var err error
 	var updateData utreexo.UpdateData
 	if uview.proofInterval == 1 {
-		err = uview.accumulator.Verify(dels, ud.AccProof, true)
+		err = uview.accumulator.Ingest(dels, ud.AccProof)
 		if err != nil {
 			return nil, err
 		}
diff --git a/blockchain/validate.go b/blockchain/validate.go
index d8e858a3..41afb81f 100644
--- a/blockchain/validate.go
+++ b/blockchain/validate.go
@@ -1075,7 +1075,7 @@ func (b *BlockChain) checkConnectBlock(node *blockNode, block *btcutil.Block,
 	// If utreexo accumulators are enabled, then check that the accumulator
 	// proof is ok.  Then convert the msgBlock.UData into UtxoViewpoint.
 	if utreexoView != nil {
-		err := utreexoView.ProcessUData(block, b.bestChain, block.MsgBlock().UData)
+		err := utreexoView.VerifyUData(block, b.bestChain, block.MsgBlock().UData)
 		if err != nil {
 			return fmt.Errorf("checkConnectBlock fail. error: %v", err)
 		}