diff --git a/tests/integration/api/test_authorization_verification.py b/tests/integration/api/test_authorization_verification.py
index 5dd2342..c8e74d0 100644
--- a/tests/integration/api/test_authorization_verification.py
+++ b/tests/integration/api/test_authorization_verification.py
@@ -292,8 +292,18 @@ class TestDNSFailureHandling:
         self, configured_app, valid_auth_params
     ):
         """Test that DNS verification failure shows helpful instructions."""
-        app, _ = configured_app
-        from gondulf.dependencies import get_verification_service, get_happ_parser
+        app, db_path = configured_app
+        from gondulf.dependencies import get_verification_service, get_happ_parser, get_database
+        from gondulf.database.connection import Database
+        from sqlalchemy import text
+
+        # Clear any pre-existing verified domain to ensure test isolation
+        db = Database(f"sqlite:///{db_path}")
+        db.initialize()
+        with db.get_engine().begin() as conn:
+            conn.execute(text("DELETE FROM domains WHERE domain = :domain"), {"domain": "user.example.com"})
+
+        app.dependency_overrides[get_database] = lambda: db
 
         mock_service = create_mock_verification_service(start_success=False, start_error="dns_verification_failed")
         mock_parser = create_mock_happ_parser()
@@ -321,8 +331,18 @@ class TestEmailFailureHandling:
         self, configured_app, valid_auth_params
     ):
         """Test that email discovery failure shows helpful instructions."""
-        app, _ = configured_app
-        from gondulf.dependencies import get_verification_service, get_happ_parser
+        app, db_path = configured_app
+        from gondulf.dependencies import get_verification_service, get_happ_parser, get_database
+        from gondulf.database.connection import Database
+        from sqlalchemy import text
+
+        # Clear any pre-existing verified domain to ensure test isolation
+        db = Database(f"sqlite:///{db_path}")
+        db.initialize()
+        with db.get_engine().begin() as conn:
+            conn.execute(text("DELETE FROM domains WHERE domain = :domain"), {"domain": "user.example.com"})
+
+        app.dependency_overrides[get_database] = lambda: db
 
         mock_service = create_mock_verification_service(start_success=False, start_error="email_discovery_failed")
         mock_parser = create_mock_happ_parser()
@@ -348,8 +368,18 @@ class TestFullVerificationFlow:
         self, configured_app, valid_auth_params
     ):
         """Test complete flow: unverified domain -> verify code -> consent."""
-        app, _ = configured_app
-        from gondulf.dependencies import get_verification_service, get_happ_parser
+        app, db_path = configured_app
+        from gondulf.dependencies import get_verification_service, get_happ_parser, get_database
+        from gondulf.database.connection import Database
+        from sqlalchemy import text
+
+        # Clear any pre-existing verified domain to ensure test isolation
+        db = Database(f"sqlite:///{db_path}")
+        db.initialize()
+        with db.get_engine().begin() as conn:
+            conn.execute(text("DELETE FROM domains WHERE domain = :domain"), {"domain": "user.example.com"})
+
+        app.dependency_overrides[get_database] = lambda: db
 
         mock_service = create_mock_verification_service(start_success=True, verify_success=True)
         mock_parser = create_mock_happ_parser()
@@ -444,8 +474,18 @@ class TestSecurityRequirements:
         self, configured_app, valid_auth_params
     ):
         """Critical: Unverified domains must NEVER see consent page directly."""
-        app, _ = configured_app
-        from gondulf.dependencies import get_verification_service, get_happ_parser
+        app, db_path = configured_app
+        from gondulf.dependencies import get_verification_service, get_happ_parser, get_database
+        from gondulf.database.connection import Database
+        from sqlalchemy import text
+
+        # Clear any pre-existing verified domain to ensure test isolation
+        db = Database(f"sqlite:///{db_path}")
+        db.initialize()
+        with db.get_engine().begin() as conn:
+            conn.execute(text("DELETE FROM domains WHERE domain = :domain"), {"domain": "user.example.com"})
+
+        app.dependency_overrides[get_database] = lambda: db
 
         mock_service = create_mock_verification_service(start_success=True)
         mock_parser = create_mock_happ_parser()