Jquery validate - check that a field exists before validating

Jquery validate - check that a field exists before validating

I have the following code, which works if the input name exists, however I have instances where one of the required fields may not even be rendered in the HTML due to not having been pulled from a DB. However I would like the JS to validate and alert the user if for example 'ui_outcome_options[client_to_contact]' hasn't been entered because it doesn't exist. I thought the below, would require the field? but this doesn't appear to be the case. Any ideas anyone? or have I missed something

var validator = $("#ui_outcome_pq").bind("invalid-form.validate", function() {
$("#outcome_errors").html("Outcome not saved. Check error(s) below.");
}).validate({
errorPlacement: function(error, element) {
error.insertBefore(element);
},
// debug: true,
errorContainer: $("#outcome_errors"),
rules: {
'ui_outcome_options[client_to_contact]': {
required: true
},
'ui_outcome_options[probate_type]': {
required: true
}
},
messages: {
'ui_outcome_options[client_to_contact]': "Please select at least one",
'ui_outcome_options[probate_type]': "Please select"
}
});