With Regard to the Distinction Between Unethical and Illegal Behaviour

Short Answer

With regard to the distinction between unethical and illegal behaviour, it is correct to say that
something that is illegal is also unethical.
a given act can be ethical, yet illegal.
the distinction between unethical and illegal behaviour has no practical significance.
it is impossible for something to be unethical and legal at the same time.
all of these are correct.