diff --git a/gtsam/geometry/Pose2.cpp b/gtsam/geometry/Pose2.cpp
index 91e915bd0..7ef7a4514 100644
--- a/gtsam/geometry/Pose2.cpp
+++ b/gtsam/geometry/Pose2.cpp
@@ -33,7 +33,7 @@ INSTANTIATE_LIE(Pose2);
 /** instantiate concept checks */
 GTSAM_CONCEPT_POSE_INST(Pose2);
 
-static const Matrix3 I3 = Eigen::Matrix3d::Identity(), Z12 = Eigen::Matrix3d::Zero();
+static const Matrix3 I3 = Eigen::Matrix3d::Identity();
 static const Rot2 R_PI_2(Rot2::fromCosSin(0., 1.));
 
 /* ************************************************************************* */