Tolleman is right about the privacy act. No private action exists. It would be a tort of intrusion upon seclusion/ invasion of privacy/ defamation. But none of them stand a very good chance, the first two barely exist in Canada and the third would face justification. If an SP outed you and your employer fired you, for example, there might be an interference with economic or contractual relations. But it would require the SP not just to out you but to send a letter to employer saying you are hiring prostitutes. But even then, you were doing the unlawful thing not the SP. If a girl outed another girl, it's more interesting. It would come down to the facts, ie what the girl is spreading about the other girl. You need a defamatory statement and an absence of defenses. If it's true it's not defamatory. Let's say a jealous SP makes a facebook profile and messages people on SP's friends list to tell them about SP's deeds. Probably no defamation there. But to the extent that the motive is to drive away a competitor, it is likely an intereference with economic relations, There is malice, there is intereference and there are damages.