Error: Unable to evaluate WHERE expression

I tried setting up a threshold alert in chronograf and the tickscript debug log shows the following error:

kapacitor Error: failed to evaluate WHERE expression

I looked at the WHERE expression and cannot see anything wrong with it but of course the error shows and the alert does not fire. I tried editing the expression by removing the double quotes for the field and replacing it with single quotes and the error went away but still the alert does not work.

var whereFilter = lambda: ("consumer_group" == "testIcon")

Can anyone help with this? This looks like an issue with kapacitor?

thanks