What texts describe a desired behavior when a personal conflict could affect a professional decision? In Academia, is there any legal text or chart commenting about the desired behavior when a personal conflict could affect a set of professional decision? 

A rough example of such chart would be a text stating that "we, academics signing this chart, engage ourselves to avoid as much as possible to let our personal tastes to influence our professional decisions, or to delegate the decisions to others if we are not certain to be able to ignore our personal tastes.". Such a chart, published by an association of academics and adopted by some universities and/or academics, would not SOLVE all instances of such problems, but would at the very least express the collective will to discourage such instances. (In the same way that a chart signed by students that they won't copy on others nor share their solution does not solve all cheating instances, but clarifies what is considered acceptable or not.)

By "professional decision", I mean a decision that you take on behalf of an institution or group of person, for which your job is to make the best decision for this institution. By "personal taste", I mean anything which applies when taking decisions for one's personal life. 
A neutral example would be a secretary having to make the "professional decision" of what food to order to department's celebration, and letting his "personal taste" influence his choice rather than his approximate knowledge of the tastes of the attendance. 
Extreme examples would be of senior faculty members using their political position to punish or reward junior members according to their personal values, independently of their professional opinion.



Broader context:

It is only human to be biased against someone with whom one had some conflicts, and only civilized to try to overcome this bias in the context of professional decisions (where one represents the choices of a community, as opposed to personal choices such as with whom you share a meal). One can think of some (uncivilized?) cultures where one does not expect anyone to even attempt to fight this bias, and of some (civilized?) cultures where letting this bias affect professional decisions (e.g. community related) would be frowned upon and considered as an abuse of power or bullying.

It used to be my opinion that academia was civilized and that most academics agreed to such an unwritten rule. It is my experience in my current setting that not only do occurrences of such conflict seem more frequent than in my previous settings, they are also considered normal there, and far from frowned upon, most often considered as "business as usual" or worse, a display of intelligence and strength. I assume that such an attitude could exist in other cultures, from other third world countries to even the US. I am wondering if Academia, which forms an international culture of its own, already has or could have a chart to curb such behavior to a more productive/collaborative/civilized one.

Note that I am not asking if some people in Academia abuse the power that their responsibilities yield (there will be in most communities), nor am I asking for general opinions about specific countries, culture and research areas. Rather I am asking if there are some reference texts which describes the desired behavior in such situation.
While I am not aware of any formal universal code (there's not much formal universal anything in academia), the generally accepted scientific ethics is that a person with a known conflict of interest should not be involved in reviewing another's scientific work or proposal.

Most scientific organizations where this might apply have explicit policies to this end.  For example:


Grant reviewers for the US National Science Foundation are not allowed to be submitters to that same call for proposals, and must recuse themselves (i.e., leave the room) when there is discussion of any recent collaborator, co-author, or person from their institution.
Journals typically ask authors to name people with known conflicts of interest who should not be asked to review.  Reviewers are also asked to declare conflicts of interest and recuse themselves, and editors are (occasionally) responsive to well-founded complaints of prejudice.
Conferences similarly ask reviewers to exclude themselves from any papers they have a conflict for, and prevent reviewers from seeing information about any paper they have a conflict of interest for.
Double-blind reviewing of any of these is intended to mitigate the effects of personal conflict, though it is often possible to identify an author anyway due to their topic and approach.


There is no responsibility to collaborate with a person you have a conflict with though, nor to ensure civil interactions at conferences, etc.

All of these systems are quite flawed, of course, and there are a lot of ways that personal conflict does leak into decisions, especially since in many cases it is difficult to distinguish from legitimate intellectual disagreement.