diff --git a/gtsam/base/TestableAssertions.h b/gtsam/base/TestableAssertions.h
index b62372957..42001b6f4 100644
--- a/gtsam/base/TestableAssertions.h
+++ b/gtsam/base/TestableAssertions.h
@@ -91,7 +91,7 @@ bool assert_equal(const std::vector<V>& expected, const std::vector<V>& actual,
   if(match) {
     size_t i = 0;
     BOOST_FOREACH(const V& a, expected) {
-      if (!assert_equal(a, expected[i++], tol)) {
+      if (!assert_equal(a, actual[i++], tol)) {
         match = false;
         break;
       }