diff --git a/traits-stubs/traits-stubs/trait_types.pyi b/traits-stubs/traits-stubs/trait_types.pyi
index 46d9543b3..00bdef73e 100644
--- a/traits-stubs/traits-stubs/trait_types.pyi
+++ b/traits-stubs/traits-stubs/trait_types.pyi
@@ -27,7 +27,6 @@ from uuid import UUID as _UUID
 
 from .trait_type import _TraitType
 
-MutableTypes: _Any
 SetTypes: _Any
 int_fast_validate: _Any
 float_fast_validate: _Any
diff --git a/traits/tests/test_constant.py b/traits/tests/test_constant.py
new file mode 100644
index 000000000..5ad091947
--- /dev/null
+++ b/traits/tests/test_constant.py
@@ -0,0 +1,54 @@
+# (C) Copyright 2005-2020 Enthought, Inc., Austin, TX
+# All rights reserved.
+#
+# This software is provided without warranty under the terms of the BSD
+# license included in LICENSE.txt and may be redistributed only under
+# the conditions described in the aforementioned license. The license
+# is also available online at http://www.enthought.com/licenses/BSD.txt
+#
+# Thanks for using Enthought open source!
+
+
+import unittest
+
+from traits.api import Constant, HasTraits, TraitError
+
+
+class TestConstantTrait(unittest.TestCase):
+
+    def test_initial_value(self):
+        class TestClass(HasTraits):
+            c_atr = Constant(5)
+
+        self.assertEqual(TestClass().c_atr, 5)
+
+    def test_mutable_initial_value(self):
+        class TestClass(HasTraits):
+            c_atr_1 = Constant([1, 2, 3, 4, 5])
+            c_atr_2 = Constant({"a": 1, "b": 2})
+
+        obj = TestClass()
+
+        self.assertEqual(obj.c_atr_1, [1, 2, 3, 4, 5])
+        self.assertEqual(obj.c_atr_2, {"a": 1, "b": 2})
+
+    def test_assign_fails(self):
+        class TestClass(HasTraits):
+            c_atr = Constant(5)
+
+        with self.assertRaises(TraitError):
+            TestClass(c_atr=5)
+        with self.assertRaises(TraitError):
+            del TestClass().c_atr
+
+    def test_mutate_succeeds(self):
+        class TestClass(HasTraits):
+            c_atr_1 = Constant([1, 2, 3, 4, 5])
+            c_atr_2 = Constant({"a": 1, "b": 2})
+
+        obj = TestClass()
+        obj.c_atr_1.append(6)
+        obj.c_atr_2["c"] = 3
+
+        self.assertEqual(obj.c_atr_1, [1, 2, 3, 4, 5, 6])
+        self.assertEqual(obj.c_atr_2, {"a": 1, "b": 2, "c": 3})
diff --git a/traits/trait_types.py b/traits/trait_types.py
index b8b33a155..b2f8bbb8b 100644
--- a/traits/trait_types.py
+++ b/traits/trait_types.py
@@ -69,7 +69,6 @@
 
 # Constants
 
-MutableTypes = (list, dict)
 SetTypes = SequenceTypes + (set,)
 
 # Numeric type fast validator definitions
@@ -1012,12 +1011,11 @@ class Constant(TraitType):
 
     Traits of this type are very space efficient (and fast) because
     *value* is not stored in each instance using the trait, but only in
-    the trait object itself. The *value* cannot be a list or dictionary,
-    because those types have mutable values.
+    the trait object itself.
 
     Parameters
     ----------
-    value : any type other than list or dict
+    value : any
         The constant value for the trait.
     **metadata
         Trait metadata for the trait.
@@ -1029,14 +1027,6 @@ class Constant(TraitType):
     #: The standard metadata for the trait:
     metadata = {"type": "constant", "transient": True}
 
-    def __init__(self, value, **metadata):
-        if type(value) in MutableTypes:
-            raise TraitError(
-                "Cannot define a constant using a mutable list or dictionary"
-            )
-
-        super(Constant, self).__init__(value, **metadata)
-
 
 class Delegate(TraitType):
     """ A trait type whose value is delegated to a trait on another object.