diff --git a/selfdrive/car/tests/test_car_interfaces.py b/selfdrive/car/tests/test_car_interfaces.py
index 742bafc76a0ce3..bb97ac8a9ad7e0 100644
--- a/selfdrive/car/tests/test_car_interfaces.py
+++ b/selfdrive/car/tests/test_car_interfaces.py
@@ -62,6 +62,7 @@ def test_car_interfaces(self, car_name, data):
 
     car_params = CarInterface.get_params(car_name, args['fingerprints'], args['car_fw'],
                                          experimental_long=args['experimental_long'], docs=False)
+    car_params = car_params.as_reader()
     car_interface = CarInterface(car_params, CarController, CarState)
     assert car_params
     assert car_interface
diff --git a/selfdrive/controls/controlsd.py b/selfdrive/controls/controlsd.py
index f147766c91ed73..416a9aa8c5979f 100755
--- a/selfdrive/controls/controlsd.py
+++ b/selfdrive/controls/controlsd.py
@@ -65,8 +65,7 @@ def __init__(self, CI=None):
     if CI is None:
       cloudlog.info("controlsd is waiting for CarParams")
       with car.CarParams.from_bytes(self.params.get("CarParams", block=True)) as msg:
-        # TODO: this shouldn't need to be a builder
-        self.CP = msg.as_builder()
+        self.CP = msg
       cloudlog.info("controlsd got CarParams")
 
       # Uses car interface helper functions, altering state won't be considered by card for actuation
diff --git a/selfdrive/controls/lib/latcontrol_torque.py b/selfdrive/controls/lib/latcontrol_torque.py
index 34b0d471241750..decff2ec054283 100644
--- a/selfdrive/controls/lib/latcontrol_torque.py
+++ b/selfdrive/controls/lib/latcontrol_torque.py
@@ -25,7 +25,7 @@
 class LatControlTorque(LatControl):
   def __init__(self, CP, CI):
     super().__init__(CP, CI)
-    self.torque_params = CP.lateralTuning.torque
+    self.torque_params = CP.lateralTuning.torque.as_builder()
     self.pid = PIDController(self.torque_params.kp, self.torque_params.ki,
                              k_f=self.torque_params.kf, pos_limit=self.steer_max, neg_limit=-self.steer_max)
     self.torque_from_lateral_accel = CI.torque_from_lateral_accel()
diff --git a/selfdrive/controls/lib/tests/test_latcontrol.py b/selfdrive/controls/lib/tests/test_latcontrol.py
index 81411edec1c3d6..e12da6ed97f20e 100644
--- a/selfdrive/controls/lib/tests/test_latcontrol.py
+++ b/selfdrive/controls/lib/tests/test_latcontrol.py
@@ -21,7 +21,7 @@ def test_saturation(self, car_name, controller):
     CI = CarInterface(CP, CarController, CarState)
     VM = VehicleModel(CP)
 
-    controller = controller(CP, CI)
+    controller = controller(CP.as_reader(), CI)
 
     CS = car.CarState.new_message()
     CS.vEgo = 30