diff --git a/src/python/dm/daq_web_service/service/experimentSessionController.py b/src/python/dm/daq_web_service/service/experimentSessionController.py
index e62999b8fb324baf4d9cc991027875ad8e0b0c15..17feb3ef2add697112a674a5c34d8f3a68a4ce61 100755
--- a/src/python/dm/daq_web_service/service/experimentSessionController.py
+++ b/src/python/dm/daq_web_service/service/experimentSessionController.py
@@ -30,7 +30,7 @@ class ExperimentSessionController(DmSessionController):
         dataDirectory = Encoder.decode(dataDirectory)
         daqInfo = {}
         encodedDaqInfo = kwargs.get('daqInfo')
-        if daqInfo is not None:
+        if encodedDaqInfo is not None:
             daqInfo = json.loads(Encoder.decode(encodedDaqInfo))
         response = self.experimentSessionControllerImpl.startDaq(experimentName, dataDirectory, daqInfo).getFullJsonRep()
         self.logger.debug('Returning: %s' % response)