>>>>If some firm asked you your opinion about me and you'd give it (either negative or positive), without my approval or request for being a reference, I'd have bad feelings about it.
>>>
>>>Negative comments are illegal in the USA and Canada as far as I know.
>>
>>They aren't illegal, it's just that most corporate human resources departments avoid them because of potential legal liability.
>
>>>>departments avoid them because of potential legal liability.
>
>Doesm't that make it a legal situation, can be taken to court?

Anything can be taken to court. That doesn't mean the plaintiff will prevail. If a person was fired for poor performance, for example, you can tell a prospective employer they were fired for poor performance. In practice most employers, at least the big ones, generally keep it to the minimum (verification of employment, dates, and title) to avoid any exposure at all to what a court might decide. But it isn't illegal to say more, as long as it's factual.