Are federal or state detectives banned from cases (i.e. murder or kidnapping) that involve a family member?

For example, physicians have long been discouraged from providing medical care for their own family members. Percival's Medical Ethics, published in 1803, argued for the separation of professional and personal identities in the care of family members. Today, the American Medical Association guidelines from the Council on Ethical and Judicial Affairs exhort physicians to refrain from treating themselves or immediate family, though it's not an outright prohibition. Is there a similar stance for law enforcement?





In this case, the victim is immediate family of the detective.





Although, would having a family member as a suspect alter an investigator's chances of working on a case?





If this is sort of work is frowned upon, who along the chain of command would enforce the policy?Are federal or state detectives banned from cases (i.e. murder or kidnapping) that involve a family member?
Normally when a family member of a law enforcement officer is involved, the person is kept from working on the case. So that the law enforcement Officer be they Federal or other would not be working the case.





Since it would be a conflict of interest situation.