First of all, that senior public servant in your hypothetical would have to disclose all of this in his report when he's appointed or, if it happens during his tenure, when he acquires it. We would deal with, then, whether this creates a conflict or not, and what the remedies are. Do you have to get rid of the company? Do you have to put it in a public trust, in a blind trust or whatever? Second, a member of the House of Commons can ask me to investigate.
In either case, I would look at it. If I find out there are reasonable grounds for there being a breach of the act, then I will launch an investigation. If I come across something that is criminal or potentially criminal, I have to refer it to the RCMP and cease my activity so that the criminal aspect, if there is any, can be resolved.