diff --git a/tests/conftest.py b/tests/conftest.py
index 8ddd2b4..08282e1 100644
--- a/tests/conftest.py
+++ b/tests/conftest.py
@@ -40,7 +40,7 @@ settings.register_profile("deterministic", settings(
     derandomize=True,
 ))
 
-if os.getenv('DETERMINISTIC_TESTS').lower == 'true':
+if os.getenv('DETERMINISTIC_TESTS').lower() == 'true':
     settings.load_profile("deterministic")
-elif os.getenv('CI').lower == 'true':
+elif os.getenv('CI').lower() == 'true':
     settings.load_profile("ci")