What can be done if a former supervisor is giving a bad review? If one suspects that their former grad studies supervisor is giving them a bad review for prospective employers or research opportunities, is there anything that can be done about it? In a country where negative recommendation letters are not legal (though they can refuse to give one).
Most job applications ask you to provide references or recommendation letters. Usually, you can choose which names you put on that list (and exclude former supervisors if you don't trust their reference).