diff --git a/libwvdrmengine/cdm/core/include/properties.h b/libwvdrmengine/cdm/core/include/properties.h
index 8840f07c..22efdfb6 100644
--- a/libwvdrmengine/cdm/core/include/properties.h
+++ b/libwvdrmengine/cdm/core/include/properties.h
@@ -85,6 +85,21 @@ class Properties {
                                     CdmClientPropertySet* property_set);
   static bool RemoveSessionPropertySet(const CdmSessionId& session_id);
 
+ protected:
+  // This function always runs the code in |Init()| (and subsequently
+  // |InitOnce()|) even if Properties have already been initialized. This is
+  // needed by certain tests that are dependent on controlling the mutable state
+  // of Properties. Should not be used in general, as most tests rely on
+  // Properties' normal guarantee about |Init()| being safe to call multiple
+  // times without destroying mutable state.
+  static void ForceReinit() {
+    {
+      std::unique_lock<std::mutex> lock(init_mutex_);
+      is_initialized_ = false;
+    }
+    Init();
+  }
+
  private:
   static CdmClientPropertySet* GetCdmClientPropertySet(
       const CdmSessionId& session_id);
@@ -111,7 +126,6 @@ class Properties {
   FRIEND_TEST(CdmLicenseTest, PrepareKeyRequestValidation);
 #endif
 
- private:
   // Called at least once before any properties are used.
   static void InitOnce();
 
diff --git a/libwvdrmengine/cdm/core/test/service_certificate_unittest.cpp b/libwvdrmengine/cdm/core/test/service_certificate_unittest.cpp
index bd936d87..aecbc92a 100644
--- a/libwvdrmengine/cdm/core/test/service_certificate_unittest.cpp
+++ b/libwvdrmengine/cdm/core/test/service_certificate_unittest.cpp
@@ -41,6 +41,11 @@ const std::string kTestSignedCertificate = a2bs_hex(
     "D2E8D5986104AACC4DD475FD96EE9CE4E326F21B83C7058577B38732CDDABC6A6BED13FB0D"
     "49D38A45EB87A5F4");
 
+class PropertiesTestPeer : public Properties {
+ public:
+  using Properties::ForceReinit;
+};
+
 }  // unnamed namespace
 
 class ServiceCertificateTest : public ::testing::Test {
@@ -75,7 +80,9 @@ class StubCdmClientPropertySet : public CdmClientPropertySet {
 
   uint32_t session_sharing_id() const override { return session_sharing_id_; }
 
-  void set_session_sharing_id(uint32_t id) override { session_sharing_id_ = id; }
+  void set_session_sharing_id(uint32_t id) override {
+    session_sharing_id_ = id;
+  }
 
   const std::string& app_id() const override { return app_id_; }
 
@@ -100,8 +107,9 @@ TEST_F(ServiceCertificateTest, InitPrivacyModeRequired) {
 
   property_set.enable_privacy_mode();
 
-  Properties::Init();
-  Properties::AddSessionPropertySet(kTestSessionId1, &property_set);
+  PropertiesTestPeer::ForceReinit();
+  ASSERT_TRUE(PropertiesTestPeer::AddSessionPropertySet(kTestSessionId1,
+                                                        &property_set));
 
   service_certificate_.Init(kTestSessionId1);
   EXPECT_FALSE(service_certificate_.has_certificate());
@@ -113,14 +121,14 @@ TEST_F(ServiceCertificateTest, InitServiceCertificatePresent) {
   property_set.enable_privacy_mode();
   property_set.set_service_certificate(kTestSignedCertificate);
 
-  Properties::Init();
-  Properties::AddSessionPropertySet(kTestSessionId1, &property_set);
+  PropertiesTestPeer::ForceReinit();
+  ASSERT_TRUE(PropertiesTestPeer::AddSessionPropertySet(kTestSessionId1,
+                                                        &property_set));
 
   std::string raw_service_certificate;
-  EXPECT_TRUE(Properties::GetServiceCertificate(kTestSessionId1,
-                                                &raw_service_certificate));
-  EXPECT_EQ(NO_ERROR,
-            service_certificate_.Init(raw_service_certificate));
+  EXPECT_TRUE(PropertiesTestPeer::GetServiceCertificate(
+      kTestSessionId1, &raw_service_certificate));
+  EXPECT_EQ(NO_ERROR, service_certificate_.Init(raw_service_certificate));
   EXPECT_TRUE(service_certificate_.has_certificate());
 }
 
@@ -129,11 +137,12 @@ TEST_F(ServiceCertificateTest, SetServiceCertificate) {
 
   property_set.enable_privacy_mode();
 
-  Properties::Init();
-  Properties::AddSessionPropertySet(kTestSessionId1, &property_set);
+  PropertiesTestPeer::ForceReinit();
+  ASSERT_TRUE(PropertiesTestPeer::AddSessionPropertySet(kTestSessionId1,
+                                                        &property_set));
 
   EXPECT_EQ(NO_ERROR, service_certificate_.Init(kTestSignedCertificate));
   EXPECT_TRUE(service_certificate_.has_certificate());
 }
 
-}
+}  // namespace wvcdm