diff --git a/hyracks/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/BTree.java b/hyracks/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/BTree.java
index 67ee936..ff94040 100644
--- a/hyracks/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/BTree.java
+++ b/hyracks/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/BTree.java
@@ -52,6 +52,7 @@
 import edu.uci.ics.hyracks.storage.am.common.api.IndexException;
 import edu.uci.ics.hyracks.storage.am.common.api.TreeIndexException;
 import edu.uci.ics.hyracks.storage.am.common.api.UnsortedInputException;
+import edu.uci.ics.hyracks.storage.am.common.exceptions.TreeIndexDuplicateKeyException;
 import edu.uci.ics.hyracks.storage.am.common.exceptions.TreeIndexNonExistentKeyException;
 import edu.uci.ics.hyracks.storage.am.common.frames.FrameOpSpaceStatus;
 import edu.uci.ics.hyracks.storage.am.common.impls.AbstractTreeIndex;
@@ -1024,9 +1025,12 @@
         protected void verifyInputTuple(ITupleReference tuple, ITupleReference prevTuple) throws IndexException,
                 HyracksDataException {
             // New tuple should be strictly greater than last tuple.
-            if (cmp.compare(tuple, prevTuple) <= 0) {
-                throw new UnsortedInputException(
-                        "Input stream given to BTree bulk load is not sorted or has duplicates.");
+            int cmpResult = cmp.compare(tuple, prevTuple);
+            if (cmpResult < 0) {
+                throw new UnsortedInputException("Input stream given to BTree bulk load is not sorted.");
+            }
+            if (cmpResult == 0) {
+                throw new TreeIndexDuplicateKeyException("Input stream given to BTree bulk load has duplicates.");
             }
         }