First up, you should resign if you're asked to do something unethical (assuming you're in a situation where you can survive for a few months while you get a new job). Because if you don't resign, you're signalling that you're okay with being asked to do things that are unethical.
As for legal recourse, yes you should consult with a lawyer if you've been asked to do something you think is illegal (they can help you report your company to the appropriate authorities). Some larger companies have internal methods of reporting issues, but given the recent activities of Wells Fargo I wouldn't recommend outing yourself as someone who is considering reporting on your company.
As for developers being held responsible, I don't think that most cases will pan out like that (it's not your job as a developer to question whether your manager has checked with your company's legal team). However you should definitely not "just follow orders" if you've been asked to do something you find to be shady or illegal.
As for legal recourse, yes you should consult with a lawyer if you've been asked to do something you think is illegal (they can help you report your company to the appropriate authorities). Some larger companies have internal methods of reporting issues, but given the recent activities of Wells Fargo I wouldn't recommend outing yourself as someone who is considering reporting on your company.
As for developers being held responsible, I don't think that most cases will pan out like that (it's not your job as a developer to question whether your manager has checked with your company's legal team). However you should definitely not "just follow orders" if you've been asked to do something you find to be shady or illegal.