diff --git a/server/etcdserver/api/membership/cluster.go b/server/etcdserver/api/membership/cluster.go
index 44c6bdef9..f022d29c4 100644
--- a/server/etcdserver/api/membership/cluster.go
+++ b/server/etcdserver/api/membership/cluster.go
@@ -303,16 +303,9 @@ func (c *RaftCluster) Recover(onSet func(*zap.Logger, *semver.Version)) {
 
 // ValidateConfigurationChange takes a proposed ConfChange and
 // ensures that it is still valid.
-func (c *RaftCluster) ValidateConfigurationChange(cc raftpb.ConfChange, shouldApplyV3 ShouldApplyV3) error {
-	var membersMap map[types.ID]*Member
-	var removedMap map[types.ID]bool
-
-	if shouldApplyV3 {
-		membersMap, removedMap = c.be.MustReadMembersFromBackend()
-	} else {
-		membersMap, removedMap = membersFromStore(c.lg, c.v2store)
-	}
-
+func (c *RaftCluster) ValidateConfigurationChange(cc raftpb.ConfChange) error {
+	// TODO: this must be switched to backend as well.
+	membersMap, removedMap := membersFromStore(c.lg, c.v2store)
 	id := types.ID(cc.NodeID)
 	if removedMap[id] {
 		return ErrIDRemoved
diff --git a/server/etcdserver/api/membership/cluster_test.go b/server/etcdserver/api/membership/cluster_test.go
index e03c19a4c..e5eb210c8 100644
--- a/server/etcdserver/api/membership/cluster_test.go
+++ b/server/etcdserver/api/membership/cluster_test.go
@@ -276,14 +276,7 @@ func TestClusterValidateAndAssignIDs(t *testing.T) {
 	}
 }
 
-func TestClusterValidateConfigurationChangeV3(t *testing.T) {
-	testClusterValidateConfigurationChange(t, true)
-}
 func TestClusterValidateConfigurationChangeV2(t *testing.T) {
-	testClusterValidateConfigurationChange(t, false)
-}
-
-func testClusterValidateConfigurationChange(t *testing.T, shouldApplyV3 ShouldApplyV3) {
 	cl := NewCluster(zaptest.NewLogger(t), WithMaxLearners(1))
 	be := newMembershipBackend()
 	cl.SetBackend(be)
@@ -464,7 +457,7 @@ func testClusterValidateConfigurationChange(t *testing.T, shouldApplyV3 ShouldAp
 		},
 	}
 	for i, tt := range tests {
-		err := cl.ValidateConfigurationChange(tt.cc, shouldApplyV3)
+		err := cl.ValidateConfigurationChange(tt.cc)
 		if err != tt.werr {
 			t.Errorf("#%d: validateConfigurationChange error = %v, want %v", i, err, tt.werr)
 		}
diff --git a/server/etcdserver/server.go b/server/etcdserver/server.go
index dd655350d..f468400b2 100644
--- a/server/etcdserver/server.go
+++ b/server/etcdserver/server.go
@@ -1967,7 +1967,7 @@ func removeNeedlessRangeReqs(txn *pb.TxnRequest) {
 // applyConfChange applies a ConfChange to the server. It is only
 // invoked with a ConfChange that has already passed through Raft
 func (s *EtcdServer) applyConfChange(cc raftpb.ConfChange, confState *raftpb.ConfState, shouldApplyV3 membership.ShouldApplyV3) (bool, error) {
-	if err := s.cluster.ValidateConfigurationChange(cc, shouldApplyV3); err != nil {
+	if err := s.cluster.ValidateConfigurationChange(cc); err != nil {
 		cc.NodeID = raft.None
 		s.r.ApplyConfChange(cc)