I have been co-supervised by my primary supervisor's wife. Suffice to say that this has been problematic where both have different research interests. Each asks me to do different jobs and they often bring their home fights to work. My primary supervisor is always submissive to her will whenever she is around. Though he supports me in every decision I do and my research behind her back. It is been a nightmare and was wondering if there are some written rules that such scenario is a conflict of interest.
Your supervisors are problematic in several ways, from what you describe:
- Pushing their own research interests over what's most beneficial to you
- Exposing you to unpleasant interpersonal issues between themselves that affect your working environment
- Not coordinating and communicating effectively with each other to co-supervise you
However, none of these things are necessarily the result of them being married. The same issues can arise (and I have seen them) with unrelated co-supervisors who do not get along.
In general, co-supervision by a married couple is not universally disallowed. (In my university it is allowed, and there is a husband-wife pair in my department that successfully co-supervises PhD students on occasion.)
Some universities do recognize this as a conflict of interest. This from the University of Western Australia (emphasis mine):
Supervision must be free of actual or perceived conflicts of interest. Supervision by, or co-supervision with, close relatives or those in close personal relationships is generally not appropriate. All such cases must be declared at the time that supervisors are nominated. In cases where approval is given on academic grounds for supervision by, or co-supervision with, close relatives or those in close personal relationships, additional supervisors who are free of an actual or perceived conflict of interest must be appointed.
I am not aware of any written rules regarding this situation.
In our department (and other affiliated departments), there are quite a few professors who are married to each other. In most cases, I have seen that such situations tend to turn out exceedingly well. However, there are, as your situation goes, many times when this can go wrong.
The best advice under these circumstances is to treat their home fights as none of your business. Stay out of it, develop your own research agenda and pursue it independent of such pettiness.
If all else fails, Don't walk ! Run !
If any conflict between a student and one of the supervisors comes up, married supervisors have a strong incentive to support each other, rather than looking out for the best interests of the students. For example, they may pressure the student to include both supervisors as authors on all publications. It's even tougher for a student to stand up to two people in positions of authority than one.
Your situation is certainly very bad, but a conflict of interest in the context of academic research is when personal interests are at stake when reporting research results (e.g. wife owns the company that manufactures the products that husband's paper say are superior to the competition).
I found this definition of a CoI on various universities websites:
A conflict of interest is a situation in which financial or other personal considerations have the potential to compromise or bias professional judgment and objectivity
The situation you describe is better described as lousy management, little respect from both supervisors towards you, and a blatant lack of professionalism from their part. However, it affects you, it certainly affects their productivity, but it's not per se a CoI. It's not like if one was reviewing the papers of the other, or was in the board that attributes funding to the wife/husband's project, etc.
My advice would be, whatever action you intend to take to get yourself out of this nightmare, not to refer to the problem as a conflict of interest. CoIs are a lot more serious than poor management and you will risk triggering the wrong type of investigation, ultimately deserving your cause.