def METHOD_NAME(session, test_name, legal_type, filing, expected_msg):
    """Assert that party is invalid."""
    registration_date = datetime(year=2020, month=6, day=10, hour=5, minute=55, second=13)
    business = factory_business('FM1234567', founding_date=registration_date, last_ar_date=None,
                                entity_type=legal_type,
                                state=Business.State.ACTIVE)
    filing['filing']['conversion']['parties'][0]['roles'] = []
    nr_res = copy.deepcopy(nr_response)
    nr_res['legalType'] = legal_type
    with patch.object(NameXService, 'query_nr_number', return_value=MockResponse(nr_res)):
        err = validate(business, filing)
    assert err
    assert err.msg[0]['error'] == expected_msg