The GWU said today that it is demanding disciplinary action by Arriva against Angela Ambury, the company's senior service standards manager, who it blamed for the unfair transfer of an interchange inspector.
The union said the inspector was transferred after she stopped Mrs Ambury's son from getting onto the bus with his dog. Animals are not allowed on the buses, except for guide dogs.
The GWU said that while the company acted promptly against ordinary workers, no action had been taken against Ms Ambury even though it protested more than a month ago.
The union said it considered the company's failure to act as discriminatory and insisted that the disciplinary code should be applied equally to everyone.