equationgirl
Respect my existence or expect my resistance
There was indeed a court case. Referee took it upon themselves to give incorrect information and the candidate had the job offer revoked. The referee was deemed to have overstepped, iirc they phoned the new employer and gave an unsolicited reference.There was a court case about it. Ex employer gave a negative reference. Employment offer was revoked for that reason. And the job seeker took it to court and won. Obviously they can still say what they want, but certain companies might be cautious about it.
It's not illegal per se to give a negative reference so long as it can be factually backed up, For example, if someone had been a poor timekeeper.
Most employers will now only confirm that an employee worked there from A to B, had X sick days over Y time period, that sort of thing. I've given personal references over the years.