You
cannot get fired for not breaking the law. I have been a professional driver - seriously, they
can’t force you to break traffic regulations. They can really, really
want you to, but there is no package so important that either it can’t be delayed the extra five minutes, or else you’ve got lights and sirens on your vehicle, and it’s perfectly legal for you to go as fast as you can.
I’ve also been a secretary, and if I was told to say that my boss was not available, it was because he was
actually not available. Maybe he was out playing golf, but he certainly wasn’t
available.
What you can do is mention in your hiring interview that you have a strong sense of ethics, and that you will always do your best to be honest and ethical in all of your business dealings. That way, if they later ask you to lie about something, or break the law in any way, you can remind them that this would go against your code of ethics.
If an employer fires you for not lying or for not breaking the law, I think you’d have a clear case to be able to sue his pants right off of him, quite frankly. The majority of employers are honest, and the few that are not, you can avoid working for simply by doing a bit of research and making sure that you apply for jobs in places that hold similar values to your own.