Quote: shouldn't an employer hiring in this country have the assumption that anyone presenting himself for work has a legal right to do so?
Sure.. unfortunately, under the Immigration Control and Reform Act, all employers are required to fill out an I-9 (Employment Eligibility Verification) form. If they don't, then they are breaking the law as well. On top of that, they generally will be paying those who do not fill out the form under the table, and all that implies.
