The case of Grant v HM Land Registry & anor is an interesting example of how the Courts will analyse workplace 'banter' and when this crosses the line into harassment and HR.
In this case, the employee was a gay man who made no secret of his sexual orientation in his former workplace. When he changed workplaces (within the same business), he decided to keep his sexuality private in the new workplace and only reveal it at a time of his choosing. A number of incidents occurred however where his sexuality was mentioned by his new (female) line manager (who was aware of his orientation) that the Claimant felt inappropriate and discriminatory.
In the first incident, a female colleague of the Claimant hinted to the line manager that she found the Claimant attractive. The response of the line manager was 'Don't go fluttering your eyelashes at him, he's gay". On the second occasion, at a dinner with a number of other people present, the line manager asked the Claimant about how his partner was doing. The tribunal found that the line manager had mentioned this as a way of drawing to the attention of others at the dinner the fact that the Claimant was gay.
The tribunal at first instance found that these incidents amounted to HR on the grounds of sexual orientation. This finding was overturned by the EAT and subsequently also by the Court of Appeal. They found that the tribunal had failed to have regard to a crucial matter; the fact that Claimant had already come out to colleagues in another office and the line manager was aware of this. While it may well be discriminatory to 'out' someone who makes it clear that they wish to keep such matters private, it is another matter when the 'gossipers' have genuine grounds for believing that the colleague has no objection to his or her status being revealed. By putting the fact of his sexuality into the public arena, the Claimant could not thereafter object if this became the subject of idle conversation and gossip.
Of course, as is often the case in such claims, much turns on the specific facts of the case. Part of what seems to have motivated the higher Courts in overturning the original decision, was the evident lack of malice or ill intent in any of the comments. Notwithstanding this decision, discussions at work that drift into areas of someone's sexuality, race, religion and so forth can often be taken the wrong way and 'jokes' that appear funny at the time can seem a lot less amusing in the cold light of day!